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  1. Curva dos valores normais de peso fetal estimado por ultra-sonografia segundo a idade gestacional

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    José Guilherme Cecatti

    Full Text Available Este trabalho teve por objetivo avaliar a evolução do peso fetal estimado em gestações normais de 20 a 42 semanas. Quanto ao desenho e métodos empregados na pesquisa, realizou-se estudo descritivo de um universo constituído por 2.874 gestantes normais da cidade de Campinas, efetuando-se exame ultra-sonográfico obstétrico de rotina com medida da biometria fetal e utilizando-se, para o cálculo do peso fetal, a fórmula de Hadlock et al. (1991. Calcularam-se os valores dos percentis 10, 50 e 90 do peso fetal, por idade gestacional, com construção de curva posteriormente alisada mediante ajuste polinomial de 2º grau. Como resultado, obteve-se que o valor do percentil 50 foi de 368 gramas na 20ª semana, 1.512 gramas na 30ª semana, atingindo 3.417 gramas na 42ª semana. Constatou-se ter havido ganho médio de 200 gramas de peso por semana, de 27 a 38 semanas, a partir de quando o incremento diminuiu. Concluiu-se que a disponibilidade de curva brasileira do peso fetal estimado normal permitirá o diagnóstico pré-natal de seus desvios pela ultra-sonografia.

  2. Avaliação do volume de fluxo venoso da bomba sural por ultra-sonografia Doppler durante cinesioterapia ativa e passiva: um estudo piloto Evaluation of venous flow volume of the calf muscle pump by Doppler ultrasound during active and passive kinesiotherapy: a pilot study

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    Carmindo Carlos Cardoso Campos

    2008-12-01

    Full Text Available CONTEXTO: O fisioterapeuta na unidade hospitalar atua sobre os efeitos da hipoatividade ou inatividade do paciente acamado. Na prática diária, a contração do músculo da panturrilha é difundida entre os profissionais de saúde no ambiente hospitalar, principalmente nos períodos de pré e pós-operatório, como forma de diminuir a estase venosa e os riscos de trombose venosa profunda nos membros inferiores. OBJETIVO: Avaliar o volume de fluxo venoso na bomba sural, através de ultra-sonografia doppler, durante cinesioterapia ativa e passiva (flexão plantar do tornozelo. MÉTODOS: A amostra foi constituída por 30 indivíduos escolhidos aleatoriamente e submetidos a ultra-sonografia doppler da veia poplítea direita, visando mensurar o volume de fluxo sanguíneo em quatro momentos: repouso, compressão manual da panturrilha, movimentação passiva e ativa do tornozelo em flexão plantar. Na análise dos resultados, utilizou-se o teste t, sendo utilizado um valor de p BACKGROUND: In-hospital physical therapists work on the effects of hypoactivity or inactivity of bedridden patients. In daily practice, contraction of the calf muscle is commonly performed by health professionals in hospitals, especially in pre- and post-operative periods as a form of reducing venous stasis and risk of deep venous thrombosis in the lower limbs. OBJECTIVE: To assess venous flow volume at the calf muscle pump using color Doppler ultrasound during active and passive kinesiotherapy (ankle plantar flexion. METHODS: The sample consisted of 30 individuals randomly selected and submitted to color Doppler ultrasound of the right popliteal vein, aiming to measure blood flow volume in four periods: rest, manual calf compression, active and passive ankle movement in plantar flexion. The t test was used for statistical analysis, and p < 0.05 was used as an index of statistical significance. RESULTS: The sample consisted of 16 females and 14 males. Means were as follows: age

  3. Curva dos valores normais de peso fetal estimado por ultra-sonografia segundo a idade gestacional

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    Cecatti,José Guilherme; Machado,Maria Regina Marrocos; Santos,Fernanda Fioravanti Azank dos; Marussi,Emílio Francisco

    2000-01-01

    Este trabalho teve por objetivo avaliar a evolução do peso fetal estimado em gestações normais de 20 a 42 semanas. Quanto ao desenho e métodos empregados na pesquisa, realizou-se estudo descritivo de um universo constituído por 2.874 gestantes normais da cidade de Campinas, efetuando-se exame ultra-sonográfico obstétrico de rotina com medida da biometria fetal e utilizando-se, para o cálculo do peso fetal, a fórmula de Hadlock et al. (1991). Calcularam-se os valores dos percentis 10, 50 e 90 ...

  4. Punção Aspirativa por Agulha Fina Orientada por Ultra-Sonografia em Lesões Não-palpáveis Fine Needle Aspiration Cytology Guided by Ultrasound in Nonpalpable Lesions

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    Cláudio Kemp

    2001-06-01

    Full Text Available Objetivo: correlacionar os achados citológicos obtidos por punção com agulha fina dirigida pela ultra-sonografia de lesões não-palpáveis da mama, císticas ou sólidas, os aspectos ultra-sonográficos e os respectivos resultados histopatológicos das lesões que foram submetidas a cirurgia. Métodos: foram analisadas 617 lesões não-palpáveis visualizadas ao ultra-som. Realizou-se a punção aspirativa por agulha fina (PAAF orientada pela ultra-sonografia, com análise citológica do material, diferenciando-as em cistos ou nódulos sólidos. Estes tiveram seu resultado citológico confrontado com o resultado histopatológico, nos casos em que foi realizada a biópsia cirúrgica. Resultados: das 617 lesões não-palpáveis, 471 eram cistos, sendo 451 cistos simples que apresentaram citologia negativa em todos os casos e 20 casos foram considerados cistos complexos. Destes, 3 (15% tiveram resultado citológico positivo ou suspeito e em 2 casos confirmou-se malignidade. Dos 105 nódulos sólidos, 63 apresentaram citologia negativa, sendo 59 concordantes com a biópsia e houve 4 casos (0,3% de resultado falso-negativo pela citologia. Todos, porém, apresentavam discordância entre imagem e citologia. Em 14 nódulos sólidos (13%, a citologia foi suspeita e, destes, 5 foram diagnosticados como carcinoma. Em outros 14 (13%, o material foi insatisfatório e 1 era carcinoma. Em 51 casos, o tríplice diagnóstico foi concordante e optou-se por seguimento clínico. Conclusão: a análise citológica do material dos cistos mamários simples é desnecessária, porém quando são complexos, a citologia é imperativa. Nas lesões sólidas não-palpáveis, é fundamental a correlação da citologia com o aspecto ultra-sonográfico e mamográfico; caso sejam discordantes, deve-se sempre prosseguir a investigação da lesão.Purpose: to determine the relationship between fine needle aspiration cytology guided by ultrasound of nonpalpable breast lesions

  5. Achados histeroscópicos em mulheres na pós-menopausa com diagnóstico de espessamento endometrial por ultra-sonografia transvaginal Hysteroscopic findings in postmenopausal women with endometrial thickening diagnosed by transvaginal ultrasound

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    Adriana Bittencourt Campaner

    2004-02-01

    Full Text Available OBJETIVO: correlacionar espessamento endometrial diagnosticado por ultra-sonografia com os achados histeroscópicos, em mulheres na pós-menopausa. MÉTODOS: foi realizado estudo transversal com avaliação histeroscópica em 121 mulheres na pós-menopausa, com diagnóstico de espessamento do endométrio por ultra-sonografia transvaginal. Das pacientes incluídas, 23 (19% recebiam diferentes esquemas de hormonioterapia e 98 não referiam uso de reposição hormnonal.; 55 pacientes queixavam-se de sangramento por via vaginal e as restantes apresentavam-se sem esta condição. Os exames endoscópicos foram realizados ambulatorialmente, utilizando-se histeroscópio rígido de 4 mm. Para a distensão da cavidade uterina empregou-se gás carbônico (CO2. Biópsia foi praticada em todas as pacientes, com auxílio de cureta tipo Novak, de 3 mm, e o material obtido submetido a estudo histopatológico. RESULTADOS: a espessura do endométrio variou entre 6 e 38 mm, com média de 10,7 ± 5,3 mm. Os achados histeroscópicos foram: lesão polipóide, em 51 pacientes (42,1%; endométrio atrófico, em 15 (12,4%; sinéquia senil, em 15 (12,4%; espessamento focal, em 13 (10,7%; lesão cerebróide, em 6 (5,0%; endométrio proliferativo, em 5 (4,1%; muco, em 5 (4,1%; mioma, em 4 (3,3%; endométrio secretor, em 3 (2,5%; hiperplasia endometrial, em 3 (2,5% e atrofia cística, em 1 (0,8%. Observou-se correlação entre os achados histeroscópicos e os resultados da histopatologia em 30 dos 51 casos de pólipo, em 12 dos 15 de endométrio atrófico e na totalidade dos casos sugestivos de hiperplasia endometrial e de adenocarcinoma. CONCLUSÃO: na maioria das pacientes, o exame histeroscópico revelou que não se tratava de real espessamento endometrial, mas sim de outras variedades de lesão da cavidade uterina.PURPOSE: to correlate endometrial thickening diagnosed by ultrasonography with hysteroscopic findings in postmenopausal women. METHODS: a transversal study

  6. Relação entre índice de resistência obtido pela ultra-sonografia Doppler transfortanela e o neurodesenvolvimento até o primeiro ano de vida em recém-nascidos a termo com encefalopatia hipóxico-isquêmica leve e moderada Relation between the resistance index obtained by the transfontanellar Doppler ultrasonography and the neurological development until the first year of life in term infants with mild or moderate hypoxic-ischaemic encephalopathy

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    Maria Helena Martins Garcia

    2007-12-01

    Full Text Available OBJETIVO: Avaliar a relação do índice de resistência (IR obtido pela ultra-sonografia Doppler transfontanela com o neurodesenvolvimento até um ano de idade, em recém-nascidos (RN a termo com encefalopatia hipóxica-isquêmica (EHI leve a moderada, secundária à asfixia intra-parto. MÉTODO: Estudo prospectivo em 20 RN com EHI leve a moderada, IR elevado no primeiro exame de Doppler, e sem doenças associadas ou anormalidades morfológicas cerebrais. Foram realizados exames seriados bimensais de Doppler transfontanela a partir do sétimo dia de vida, e avaliações clínicas mensais do neurodesenvolvimento no primeiro ano de vida. RESULTADOS: Houve normalização progressiva dos valores de IR até o último exame realizado. Cinco pacientes apresentaram normalização clínico-neurológica no período neonatal, após o primeiro exame de Doppler. Quinze lactentes apresentaram alterações neurológicas com resolução a partir do segundo trimestre de vida. CONCLUSÃO: Houve relação entre os períodos em que ocorreu a normalização dos valores de IR e a melhora clínica-neurológica.OBJECTIVE: To evaluate the relation between the resistance index (RI obtained by transfontanellar Doppler ultrasonography, and the neurodevelopment until one year of life, at term newborns with mild or moderate hypoxic-ischaemic encephalopathy due to intrapartum asphyxia. METHOD: 20 term newborns, with mild or moderate hypoxic-ischemic encephalopathy, high values of resistance index in the first exam, and without cerebral morfologic abnormalities or other diseases. They were submitted to serial bimonthly transfontanellar Doppler ultrasonography, from the seventh day of life on, and monthly clinical neurodevelopment assessment until one year of life. RESULTS: There was a progressive normalization of RI values until the last examination. In five cases there were clinical neurologic normalization in the neonatal period after the first Doppler exam. Fifteen infants

  7. Medida da espessura do segmento uterino inferior em gestantes com cesárea prévia: análise da reprodutibilidade intra- e interobservador por ultra-sonografia bi- e tridimensional Lower uterine segment thickness measurement in pregnant women with previous caesarean section: intra- and interobserver reliability analysis using bi- and tridimensional ultrasonography

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    Daniela de Abreu Barra

    2008-03-01

    Full Text Available OBJETIVO: comparar a reprodutibilidade intra- e interobservador da medida da espessura total do segmento uterino inferior (SUI, por via abdominal, e da medida da camada muscular, por via vaginal, usando ultra-sonografia bi- e tridimensional. MÉTODOS: foi estudada a medida da espessura do SUI de 30 gestantes com cesárea anterior, entre a 36ª e a 39ª semanas, por dois observadores. Foi efetuada abordagem ultra-sonográfica abdominal com a paciente em posição supina e vaginal em posição de litotomia. No corte sagital, foi identificado SUI e foram coletadas quatro imagens bidimensionais e dois blocos tridimensionais da espessura total por via abdominal e o mesmo da camada muscular por via vaginal. As aquisições tridimensionais foram manipuladas no modo multiplanar. O tempo foi cronometrado. A reprodutibilidade foi avaliada pelo cálculo da diferença absoluta entre todas as medidas, proporção de diferenças menores que 1 mm, coeficiente de correlação intraclasse (ICC e limites de concordância de Bland e Altman. RESULTADOS: a medida da espessura média do SUI por via abdominal bidimensional foi de 7,4 mm e, por via vaginal, de 2,7 mm; a tridimensional foi 6,9 mm abdominal e 5,1 mm vaginal. Reprodutibilidade intra- e interobservador da via vaginal versus abdominal: menor diferença absoluta (0,2-0,4 versus 0,8-1,5 mm, maior proporção de diferenças (85,8-97,8 versus 48,7-72,8% com p0,05 e menores limites de concordância (-3,8 a 3,4 versus -3,6 a 4 mm para ultra-sonografia tridimensional e ICC semelhantes (0,6-0,9 versus 0,7-0,9. CONCLUSÕES: do exposto, concluímos que a medida da espessura da camada muscular do SUI por via vaginal utilizando a ultra-sonogafia tridimensional é mais reprodutível. Nossos resultados, porém, não indicam que essa medida tenha implicação clínica para predição de rotura uterina, que não foi objeto deste estudo. O único trabalho que correlacionou a espessura do SUI com risco de rotura uterina, sem

  8. Ultra-sonografia tridimensional em ginecologia: malformações uterinas Three-dimensional ultrasound in gynecology: uterine malformations

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    Adilson Cunha Ferreira

    2007-04-01

    Full Text Available As malformações uterinas são achados pouco comuns na clínica ginecológica. As estatísticas nesta área são muito falhas. Corrobora, ainda, a falta de uniformização na terminologia empregada e as dificuldades diagnósticas. A partir da década de oitenta, a ultra-sonografia tornou-se um procedimento indispensável à prática toco-ginecológica, contribuindo e modificando conceitos e procedimentos dentro dessa especialidade. O advento dos transdutores endocavitários, a análise com Doppler colorido de amplitude e espectral, assim como a melhoria crescente da qualidade de imagem contribuíram para isso. Nos últimos dez anos muito se tem pesquisado, publicado e discutido sobre o papel da ultra-sonografia tridimensional. Os autores fazem uma revisão do tema e ressaltam a importância dessa metodologia como modalidade diagnóstica.Uterine malformations are unusual findings in the clinical practice of gynecology. Statistics regarding this abnormality are flawed, and there is a lack of standardization of the pertinent terminology, besides difficulty in the diagnosis. Starting in the 1980's, ultrasound became a procedure indispensable to the clinical practice in the field of tocogynecology, modifying concepts and procedures, and bringing an important contribution to this specialty. The advent of endocavitary transducers, amplitude and spectral color Doppler, as well as the increasing improvement in the imaging quality, has contributed to this progress. Over the last ten years, much has been studied, published and discussed about the role of the three-dimensional ultrasonography. The authors review the topic and emphasize the importance of this method as a diagnostic modality.

  9. Validação da curva normal de peso fetal estimado pela ultra-sonografia para o diagnóstico do peso neonatal

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    Cecatti José Guilherme; Machado Maria Regina Marrocos; Krupa Fabiana da Graça; Figueiredo Priscila Garcia; Pires Helaine Maria Besteti

    2003-01-01

    OBJETIVO: avaliar a concordância entre o peso fetal estimado (PFE) por ultra-sonografia e o neonatal, o desempenho da curva normal de PFE por idade gestacional no diagnóstico de desvios do peso fetal/neonatal e fatores associados. MÉTODOS: participaram do estudo 186 grávidas atendidas de novembro de 1998 a janeiro de 2000, com avaliação ultra-sonográfica até 3 dias antes do parto, determinação do PFE e do índice de líquido amniótico e parto na instituição. O PFE foi calculado e classificado d...

  10. Acurácia diagnóstica do espessamento ecogênico periportal à ultra-sonografia e da histopatologia no diagnóstico diferencial da atresia biliar

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    Roquete,Mariza L. V.; Ferreira,Alexandre R.; Fagundes,Eleonora D. T.; Castro,Lúcia P. F.; Silva,Rogério A. P.; Penna,Francisco J.

    2008-01-01

    OBJETIVOS: Definir a sensibilidade, especificidade e a acurácia do espessamento ecogênico periportal à ultra-sonografia e da histopatologia hepática, isolados ou em conjunto, na distinção diagnóstica entre atresia biliar e as colestases intra-hepáticas. MÉTODOS: Trata-se de estudo retrospectivo realizado entre janeiro de 1990 e dezembro de 2004. Foram analisados 51 casos de atresia biliar e 45 com colestase intra-hepática. A histopatologia foi realizada por uma patologista de forma cega. O es...

  11. Pancreatite aguda leve: avaliação pela ultra-sonografia. estudo prospectivo Mild acute pancreatitis: ultrasound evaluation: a prospective study

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    Márcio Martins Machado

    2002-07-01

    Full Text Available Resumo Neste estudo foram avaliados, por meio da ultra-sonografia, 21 pacientes com pancreatite aguda leve. Foram analisadas a presença ou ausência de hipoecogenicidade do pâncreas e a presença ou ausência de líquido peripancreático. Em 19 pacientes (90,5% foi identificada hipoecogenicidade pancreática, e em três (15,8% destes pacientes foi identificada a presença de pequena quantidade de líquido na pequena cavidade dos epíploons. Em dois pacientes (9,5% não se identificou qualquer alteração pancreática. Com relação à possível etiologia da pancreatite aguda, em 15 pacientes (71,5% pôde-se demonstrar a presença de colecistopatia calculosa, em quatro pacientes (19,0% havia história de alcoolismo crônico e não foram identificados cálculos na vesícula biliar, e em dois pacientes (9,5% não foi identificada qualquer causa aparente. Os autores concluem que a ultra-sonografia pode identificar alteração na maioria dos pacientes com pancreatite aguda leve e permite, ainda, o acompanhamento daqueles com pequenas coleções líquidas peripancreáticas.We analyzed the ultrasonographic findings of 21 patients with mild acute pancreatitis. The presence or absence of pancreatic hypoechogenicity and peripancreatic fluid collection was assessed. Pancreatic hypoechogenicity was identified in 19 patients (90.5% whereas small sac fluid collection was identified in 3 (15.8% of these patients. No abnormality was seen in 2 patients (9.5%. Regarding the etiology of acute pancreatitis, cholelithiasis was identified in 15 patients (71.5%, alcohol abuse was identified in 4 patients (19.0%, and in 2 patients (9.5% no probable etiology could be found. The authors conclude that ultrasonography may identify abnormalities in the majority of patients with mild acute pancreatitis and can be used to assess patients with peripancreatic fluid collections.

  12. Papel da ultra-sonografia na avaliação da efusão pleural The role of ultrasound in the assessment of pleural effusion

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    Adilson Cunha Ferreira

    2006-04-01

    Full Text Available A efusão pleural, antigamente denominada derrame pleural, é caracterizada pelo acúmulo de líquido no espaço pleural, em decorrência do desequilíbrio entre formação e reabsorção de fluido ou por alteração na drenagem linfática. O propósito desta revisão foi estabelecer a importância da aplicação da ultra-sonografia no diagnóstico de efusão pleural. Os autores discutem a aplicação da ultra-sonografia no diagnóstico e abordagem terapêutica dessa entidade, e ressaltam sua importância nas doenças do tórax, vantagens, limitações e desvantagens em relação a radiografia simples, tomografia computadorizada e exame físico. Discutem, ainda, o conceito de efusão pleural, sua fisiopatologia, morbidade, mortalidade, principais causas e apresentação clínica. A técnica de realização do exame é sistematicamente abordada, tanto pela via torácica quanto abdominal.The pleural effusion, formerly called pleural spill, is an accumulation of fluid in the pleural space, as a consequence of an imbalance between the formation and reabsorption of such fluid, or due to an alteration in the drainage to lymph nodes. The purpose of this bibliographic review is to establish the importance of the use of ultrasound in pleural diffusion diagnosis. The authors discuss the use of ultrasonography in the diagnosis and therapeutic approach of this disease, and stress the importance of ultrasonography in chest diseases diagnosis, its advantages, limitations and disadvantages when compared to the common x-ray, computed tomography and physical examination. The authors also discuss the definition of pleural effusion, its physiopathology, morbidity, mortality, main causes and clinical presentation. The examination technique is systematically approached both by thoracic and abdominal pathways.

  13. Valor da ultra-sonografia na avaliação das alterações endometriais em pacientes tratadas com tamoxifeno Value of sonographic endometrial findings in patients under tamoxifen therapy

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    Arildo Corrêa Teixeira

    2007-12-01

    Full Text Available OBJETIVO: Avaliar as alterações endometriais por meio da ultra-sonografia transvaginal e correlacioná-las com os achados da histeroscopia e histologia, em pacientes submetidas a tratamento com tamoxifeno. MATERIAIS E MÉTODOS: No período de janeiro de 2003 a dezembro de 2005, foram incluídas pacientes com câncer de mama usuárias de tamoxifeno que apresentaram espessamento endometrial acima de 5 mm. Os achados foram correlacionados com os dados de histeroscopia e anatomopatologia. RESULTADOS: Foram selecionadas 25 pacientes com idade média de 62,6 anos. O tempo médio do diagnóstico do câncer foi de 4,3 anos e do uso de tamoxifeno, três anos. Vinte pacientes eram assintomáticas (80% e as demais apresentaram sangramento (20%. À ultra-sonografia, 16% apresentaram espessamento endometrial entre 5 mm e 8 mm, 40% entre 9 mm e 15 mm, e 44% acima de 15 mm. Ao estudo com a histeroscopia, 40% apresentaram atrofia, 16% atrofia cística, 28% pólipos, e 16% lesão hiperplásica. O estudo anatomopatológico apresentou-se normal em 35,2% dos casos e mostrou atrofia em 5,8%, pólipo em 29,4% e hiperplasia em 11,7%. Foi observado um caso de adenocarcinoma (5,8%. CONCLUSÃO: A ultra-sonografia associada à histeroscopia apresentam-se como importantes aliados na avaliação de pacientes usuárias de tamoxifeno. A detecção de espessamento endometrial à ultra-sonografia apresenta baixa especificidade, enquanto a histeroscopia é mais acurada na detecção de pólipos, hiperplasia e alterações neoplásicas.OBJECTIVE: To evaluate endometrial alterations by means of transvaginal ultrasound and to correlate them with hysteroscopic and histological findings in patients under tamoxifen therapy. MATERIALS AND METHODS: The present study was developed in the period between January 2003 and December 2005, including patients under tamoxifen therapy for breast cancer, and presenting with endometrial thickening > 5 mm. The sonographic findings were correlated

  14. Uso da ultra-sonografia na triagem de disrafismos espinhais ocultos Screening of occult spinal dysraphism by ultrasonography

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    José Gilberto de Brito Henriques

    2004-09-01

    Full Text Available O uso da ultra-sonografia para diagnóstico de lesões da coluna vertebral é difundido desde a década de oitenta. Suas aplicações envolvem: diagnóstico de lesões medulares traumáticas; uso intra-operatório em cirurgias do trauma e tumores medulares; uso pré-operatório e evolutivo em pacientes com disrafismos espinhais; diagnóstico pré-natal dos disrafismos; diagnóstico dos disrafismos espinhais ocultos ao nascimento. Pacientes com suspeita de disrafismo espinhal oculto (estigmas cutâneos em linha média ou história familiar de disrafismos representaram a principal indicação do exame que foi realizado em 292 pacientes do Hospital das Clínicas da Universidade Federal de Minas Gerais. Alterações como lipomas do cone medular, medula baixa, filo terminal espesso, cistos da ponta do cone medular e seios dérmicos foram identificados com fidelidade à ultra-sonografia. A interpretação do exame não apresentou dificuldades técnicas. Sua realização é rápida, não é necessária sedação, apresenta baixo custo e idealmente deve ser realizado pelo próprio neurocirurgião devido ao grande número de informações possíveis durante o exame. O exame entretanto não substitui a ressonância magnética mas pode ser um bom método de triagem para os pacientes.Ultrasonography for diagnosis of spinal cord diseases has been used since the eighties. There are different fields for its use: traumatic spine lesions, intra-operative use in trauma and spine tumors surgery, pre-operative and follow up study for spinal dysraphism, occult spinal dysraphism of the newborn. Patients with suspected occult spinal dysraphism are the most important indication for the method. Utrasonography was performed in 292 patients of Hospital das Clínicas, Universidade Federal de Minas Gerais. Lesions such as conus medullaris lipomas, low level of conus medullaris, filum terminale tethering, cauda equina cysts and dermal sinuses can be well demonstrated. There

  15. Importância da ultra-sonografia anorretal tridimensional na decisão terapêutica da endometriose profunda Importance of the three-dimensional anorectal ultrasonography in deep endometriosis

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    Univaldo Etsuo Sagae

    2009-12-01

    Full Text Available OBJETIVO: Este estudo visa demonstrar a importância da ultra-sonografia anorretal tridimensional (US 3D no diagnóstico da endometriose profunda e o grau de acometimento do trato intestinal na decisão terapêutica da endometriose do septo retovaginal. MÉTODOS: Estudo prospectivo realizado entre março de 2007 e julho de 2009. Sessenta e cinco mulheres com endometriose pélvica e com queixas gastrointestinais foram avaliadas e submetidas a US 3D. Vinte pacientes, média de idade 33,7anos, com suspeita de foco endometriótico intestinal foram submetidas ao procedimento laparoscópico para a realização de inventário da cavidade abdominal e tratamento cirúrgico. RESULTADOS: Em dezenove mulheres (95%, os achados laparoscópicos confirmaram a presença do foco endometriótico retal. O procedimento realizado à laparoscopia foi: exérese de foco peritoneais (n= 1; ressecção parcial do retossigmóide (n= 9; exérese de nódulo de reto (n= 10. O tempo operatório médio por procedimento foi de 120 minutos. O tempo médio de alta foi 1,7 dias. Duas pacientes apresentaram como complicação o aparecimento de fistula retovaginal. CONCLUSÃO: Conclui-se que a ultra-sonografia anorretal tridimensional é exame específico na avaliação do segmento anorretal, decisivo na detecção de focos endometrióticos do septo retovaginal e avalia eventuais doenças associadas nesse segmento, determinando a estratégica terapêutico-cirúrgica adequada.OBJECTIVE: This study aims to demonstrate the importance of three-dimensional anorectal ultrasonography (US 3D in the diagnosis of deep endometriosis and level of intestinal involvement in the decision of the therapy of endometriosis of rectovaginal septum. METHODS: A prospective study between March 2007 and July 2009. Sixty-five women with pelvic endometriosis and gastrointestinal complaints were evaluated and submitted to 3D U.S.. Twenty patients, mean age 33.7 years, with suspected of intestinal endometriosis

  16. Evolução do comprimento cervical uterino na gestação, avaliado pela ultra-sonografia transvaginal Changes in cervical length during pregnancy measured by transvaginal ultrasound

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    Reginaldo Antônio de Oliveira Freitas-Júnior

    2003-03-01

    Full Text Available OBJETIVO: analisar a evolução do comprimento cervical uterino, ao longo da gestação, avaliado por meio da ultra-sonografia transvaginal. MÉTODOS: foi realizado estudo prospectivo, longitudinal, no qual 82 gestantes hígidas foram acompanhadas desde o início da gestação, das quais 49 mantiveram o seguimento até o parto sem complicações da gravidez, sendo examinadas a cada quatro semanas, e agrupadas, conforme a paridade, em nulíparas ou com um ou mais partos anteriores. O comprimento do colo uterino foi avaliado em vista sagital pela ultra-sonografia transvaginal, com a medida linear da distância entre os orifícios cervicais interno e externo. RESULTADOS: as médias de comprimento do colo uterino, bem como os percentis 5, 25, 50, 75 e 95, em função da idade gestacional, não diferiram significativamente entre os grupos estudados (p>0.05. No intervalo entre a 20ª e a 24ª semana gestacional o comprimento cervical variou entre 28, 35 e 47,2 mm, com os percentis 5, 50 e 95, respectivamente. O comprimento cervical uterino diminuiu progressivamente ao longo da gestação normal, sendo esse encurtamento significativo após a 20ª semana de gravidez e mais expressivo após a 28ª semana (pPURPOSE: to establish a normality curve of cervical length during pregnancy measured by transvaginal ultrasonography. METHODS: we conducted a prospective, longitudinal study on 82 healthy pregnant women who were followed up from the beginning of pregnancy to delivery at four-week intervals, of whom 49 concluded the study. Patients were divided according to parity into nulliparous women and women with one or more previous deliveries. Cervical length was measured in a sagittal view by transvaginal ultrasonography, as the linear distance between internal and external cervical os. RESULTS: no significant difference was observed in mean cervical length or the 5th, 25, 50th, 75th, or 95th percentile according to gestational age between groups (p>0

  17. Amadurecimento precoce da placenta avaliada pela ultra-sonografia e prognóstico perinatal Early placental maturation evaluated by ultrasound and perinatal prognosis

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    Ana Patrícia Santos de Queiroz

    2006-03-01

    Full Text Available OBJETIVO: descrever os resultados maternos e perinatais das gestações com amadurecimento precoce da placenta detectado pela ultra-sonografia. MÉTODOS: realizou-se estudo retrospectivo, descritivo, tipo série de casos, com comparação de grupos. Foram incluídas 146 gestantes, internadas entre janeiro de 2000 e dezembro de 2002 e em cujo prontuário constavam diagnóstico de amadurecimento precoce da placenta (presença de placenta grau II antes da 32ª semana de gestação ou grau III, antes da 35ª semana de gestação e descrição das condições materno-fetais. Foram excluídas gestantes com diagnóstico de: amniorrexe prematura, gravidez múltipla, forma aguda de descolamento prematuro de placenta normoinserida e malformação fetal. As complicações clínico-obstétricas foram: doenças hipertensivas, redução do crescimento intra-uterino, alterações do volume de líquido amniótico, infecções, diabete materno, anemia falciforme, soropositividade para HIV, drogadição, litíase renal, epilepsia e asma brônquica. Pelos prontuários, foram identificadas 106 gestantes com complicações clínico-obstétricas (Gcom e 40, sem essas complicações (Gsem. Para comparação entre os grupos, empregaram-se os testes de chi2 e exato de Fisher, ao nível de significância de 0,05. RESULTADOS: o grupo Gcom apresentou maior freqüência de oligoâmnio (27,3%, restrição de crescimento intra-uterino (44,3% e cesárea antecedente ao trabalho de parto (36,8%. Comparado ao grupo Gsem, o Gcom caracterizou-se por maior incidência de óbitos fetais, prematuros (58,8 versus 40%, menor índice de Apgar de 5º minuto, peso ao nascer PURPOSE: to describe perinatal and obstetric characteristics of pregnant women with ultrasonographic early placental aging. METHODS: using a retrospective, descriptive, series of cases, with group comparison, the authors analyzed the data of 146 pregnant women, whose diagnosis of placental early aging (presence of grade

  18. Aspectos morfológicos da ultra-sonografia hepática de ovinos Morphologic aspects of hepatic ultrasonography in sheep

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    Pedro B. Néspoli

    2009-04-01

    Full Text Available A ultra-sonografia (US é uma das técnicas de exame complementar eletivas para o diagnóstico de enfermidades hepáticas de diversas espécies domésticas. Em ovinos, no entanto, existem poucos relatos sobre o aspecto ultra-sonográfico de enfermidades hepáticas e não há definição precisa dos padrões anatômicos da US normal do fígado. Neste estudo foram utilizados 58 ovinos da raça Santa Inês: n1=8 machos, n2=10 fêmeas não gestantes e n3=40 fêmeas gestantes. Os animais foram escaneados do 12º ao 8º espaços intercostais (EI para se observar a localização da veia cava caudal (VC, veia porta (VP e vesícula biliar (VB e para se aferir a espessura do fígado sobre a VC e VP no 11º e 10º EI. O fígado foi examinado de forma satisfatória do 12º até o 8º EI. Nesta área, tanto a VC como a VP, foram observadas do 12º ao 9º EI, porém a VC não foi examinada de forma adequada em 11 animais, 10 com peso acima de 50kg. Entre os dois grupos de fêmeas, a VC e a VP foram observadas com maior freqüência no 11º e 10º EI e em todos os machos examinados do 12º ao 10º EI. A localização da vesícula biliar oscilou entre o 10º e o 8º EI, com maior incidência a nível do 9º e 8º EI nas fêmeas gestantes e não gestantes, e sobre o 9º EI nos machos. Comparativamente, a ecogenicidade do parênquima hepático foi mais intensa do que a do córtex renal. Houve correlação significativa entre o peso do fígado e a espessura hepática sobre a veia porta no 11º e o 10º EI no grupo de fêmeas gestantes. A US forneceu informações importantes quanto a topografia e ecogenicidade do fígado e mostrou ser uma ferramenta útil para estimar o peso do órgão.The ultrasonography (US is a complementary technique of choice for the diagnostic of hepatic diseases in many domestics' species. In sheep however there are few reports about ultrasonography in hepatic diseases and there is not precise definition about the anatomic standards of

  19. Acurácia diagnóstica da histerossalpingografia e da ultra-sonografia para avaliação de doenças da cavidade uterina em pacientes com abortamento recorrente Diagnostic accuracy of hysterosalpingography and transvaginal sonography to evaluate uterine cavity diseases in patients with recurrent miscarriage

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    Évelyn Traina

    2004-01-01

    Full Text Available OBJETIVO: avaliar a acurácia da histerossalpingografia e da ultra-sonografia transvaginal bidimensional para o diagnóstico de defeitos uterinos em pacientes com aborto recorrente. MÉTODOS: oitenta pacientes com história de dois ou mais abortos espontâneos consecutivos foram submetidas a histerossalpingografia, ultra-sonografia bidimensional pélvica e transvaginal e histeroscopia ambulatorial. Os achados foram divididos em três grupos: alterações da forma, sinéquias e lesões polipóides. A histeroscopia foi considerada padrão-ouro. A concordância entre os diferentes métodos foi avaliada pelo coeficiente kappa e sua significância foi testada. O nível de significância adotado foi de 0,05 (alfa=5%. Sensibilidade, especificidade, valores preditivos positivo e negativo, com intervalos de confiança de 95%, foram calculados. RESULTADOS: defeitos cavitários foram diagnosticados em 29 (36,3% pacientes, sendo 11 (13,7% alterações da forma, 17 (21,3% sinéquias e uma (1,3% lesão polipóide. A concordância global da histerossalpingografia com a histeroscopia foi de 85,0%, ao passo que da ultra-sonografia foi de apenas 78,7%. Os melhores resultados da histerossalpingografia foram obtidos para os diagnósticos de alterações da forma e sinéquias (acurácia de, respectivamente, 97,5 e 95%. Para lesões polipóides, a histerossalpingografia teve acurácia de apenas 92,5%, devido ao baixo valor preditivo positivo (14,3%. A ultra-sonografia teve acurácia inferior para todos os diagnósticos, 93,7% para alterações da forma e 85% para detecção de sinéquias, às custas principalmente de baixa sensibilidade. CONCLUSÕES: a histerossalpingografia revelou boa acurácia diagnóstica para a pesquisa da cavidade uterina em pacientes com aborto recorrente. A ultra-sonografia mostrou especificidade alta, porém com baixa sensibilidade.PURPOSE: to evaluate the diagnostic accuracy of hysterosalpingography (HSG and transvaginal sonography (TVS in

  20. Acurácia diagnóstica do espessamento ecogênico periportal à ultra-sonografia e da histopatologia no diagnóstico diferencial da atresia biliar Accuracy of echogenic periportal enlargement image in ultrasonographic exams and histopathology in differential diagnosis of biliary atresia

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    Mariza L. V. Roquete

    2008-08-01

    Full Text Available OBJETIVOS: Definir a sensibilidade, especificidade e a acurácia do espessamento ecogênico periportal à ultra-sonografia e da histopatologia hepática, isolados ou em conjunto, na distinção diagnóstica entre atresia biliar e as colestases intra-hepáticas. MÉTODOS: Trata-se de estudo retrospectivo realizado entre janeiro de 1990 e dezembro de 2004. Foram analisados 51 casos de atresia biliar e 45 com colestase intra-hepática. A histopatologia foi realizada por uma patologista de forma cega. O espessamento ecogênico periportal foi pesquisado na ultra-sonografia como único sinal diagnóstico de atresia biliar. Foram calculados os índices de sensibilidade, especificidade e acurácia do espessamento ecogênico periportal e da histologia isoladamente ou associados. O padrão-ouro utilizado para o diagnóstico de atresia biliar foi o aspecto da via biliar extra-hepática à laparotomia. RESULTADOS: O espessamento ecogênico periportal revelou sensibilidade de 49%, especificidade de 100% e acurácia de 72,5%. A histopatologia compatível com obstrução biliar extra-hepática conferiu sensibilidade de 90,2%, especificidade de 84,6% e acurácia de 87,8%. O espessamento ecogênico periportal e a histopatologia isolados ou associados proporcionaram sensibilidade de 93,2%, especificidade de 85,7% e acurácia de 90,3%. CONCLUSÕES: A evidência do espessamento ecogênico periportal na ultra-sonografia é indicação de laparotomia. Se o espessamento ecogênico periportal é negativo, está indicada a biopsia hepática; se a histopatologia revelar sinais de atresia biliar, impõe-se a laparotomia exploradora. Nos casos de espessamento ecogênico periportal negativo com histopatologia de hepatite neonatal ou de outras colestases intra-hepáticas, recomenda-se o acompanhamento ou o tratamento clínico conforme o diagnóstico.OBJECTIVES: To define the sensitivity, specificity and accuracy of the ultrasound triangular cord sign and hepatic

  1. Fatores maternos associados ao peso fetal estimado pela ultra-sonografia Maternal factors associated with fetal weight estimated by ultrasonography

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    Adriana Suely de Oliveira Melo

    2008-09-01

    Full Text Available OBJETIVO: avaliar o efeito de variáveis maternas, socioeconômicas e obstétricas, assim como a presença de incisuras na 20ª e na 24ª semana, sobre o peso fetal estimado no final da gravidez (36ª semana em gestantes atendidas pelo Programa Saúde da Família em uma cidade do interior do Nordeste do Brasil. MÉTODOS: estudo longitudinal incluindo 137 gestantes. As gestantes foram acompanhadas a cada quatro semanas para aferição das condições clínicas, socioeconômicas e obstétricas, incluindo o peso materno. As artérias uterinas foram avaliadas pelo Doppler na 20ª e 24ª semana, o peso fetal e o índice de líquido amniótico (ILA foram determinados na 36ª semana. O estado nutricional materno inicial foi determinado pelo índice de massa corpórea (IMC, classificando-se as gestantes como com baixo peso, eutróficas, com sobrepeso e obesas. O ganho ponderal durante a gestação foi avaliado de acordo com o estado nutricional inicial, sendo ao final do segundo e terceiro trimestre classificado em ganho ponderal insuficiente, adequado e excessivo. Foi realizada análise de variância para avaliar a associação do peso fetal estimado na 36ª semana com as variáveis preditoras, ajustada por regressão linear múltipla. RESULTADOS: observou-se associação entre peso fetal estimado na 36ª semana e idade da mãe (p=0,02, trabalho materno (p=0,02, estado nutricional inicial (p=0,04, ganho ponderal no segundo trimestre (p=0,01, presença de incisuras nas artérias uterinas (p=0,02 e ILA (p=0,007. Os principais fatores associados ao peso fetal estimado na 36ª semana, após a análise de regressão múltipla, foram: IMC no início da gravidez, ganho ponderal no segundo trimestre, ILA e tabagismo. CONCLUSÕES: o peso fetal no presente estudo associou-se positivamente ao estado nutricional materno inicial, ao ganho ponderal no segundo trimestre, ao volume do líquido amniótico e negativamente ao hábito de tabagismo.PURPOSE: to evaluate the

  2. Ultra-sonografia na artrite reumatóide: aplicabilidade e perspectivas Ultrasonography in rheumatoid arthritis: applicability and expectations

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    Eloy de Ávila Fernandes

    2008-02-01

    Full Text Available Este trabalho realiza uma revisão bibliográfica sobre o papel do ultra-som (US no diagnóstico precoce da artrite reumatóide (AR, sua utilização no tratamento destes pacientes e sua utilidade na avaliação da resposta ao tratamento. A AR é uma doença inflamatória crônica que, quando não diagnosticada e tratada adequadamente, pode levar à deformidade física e à incapacidade para o trabalho. A introdução precoce das drogas modificadoras da doença (DMCD, sejam elas tradicionais ou mais novas (agentes biológicos, pode modificar a evolução da doença. Para tanto, o diagnóstico da AR precisa ser feito o mais rápido possível. O US é um método que possibilita o estudo das articulações e pode mostrar sinais de atividade inflamatória, especialmente a sinovite. Técnicas como o estudo com Doppler colorido e o Doppler de amplitude podem ajudar na avaliação de atividade da doença, diferenciando tecido inflamatório ativo (pannus de inativo. Outros achados como erosões, alterações tendíneas, bursites, cistos sinoviais e derrames articulares também podem ser encontrados. Esta revisão, no entanto, demonstra que métodos de quantificação da atividade inflamatória ainda precisam ser estabelecidos no US.This review discusses the usefulness of ultrasound in the early diagnosis of reumathoid arthritis, its utilization in these patients treatment and its utility in evaluation of the response to treatment. Reumathoid arthritis is a chronic disease that when it is not promptly diagnosed it can cause physical deformity and disability to work. The early introduction of disease modifying antirheumatic drugs (DMARDs, no matter traditional or newer (biologic agents, may modify the disease outcome. In order that , the diagnosis of RA must be made as soon as possible. Ultrasound makes possible to study the joints and can show signs of inflammatory activity, especially synovitis. Color Doppler and power Doppler can help differentiate

  3. Diagnóstico de cistos ovarianos pela palpação de ultra-sonografia transretal em fêmeas suínas: relato de dois casos clínicos

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    VIANA, Carlos Henrique Cabral; ARRUDA, Rubens Paes de; MORETTI, Anibal Saint'Anna; VISINTIN, José Antonio

    1998-01-01

    Foram abordados alguns conceitos sobre a fisiopatologia e a semiologia de cistos ovarianos em fêmeas suínas, descrevendo-se dois casos clínicos, um sintomático e outro assintomático. No caso sintomático, observou-se infertilidade, cios irregulares, edema de vulva e clitóris aumentado de volume. À palpação retal, constataram-se cistos em ambos os ovários da fêmea com sintomas e um cisto no ovário esquerdo da assintomática. A ultra-sonografia possibilitou visualizar, assim como avaliar com prec...

  4. Avaliação ultra-sonográfica e ao Doppler dos TIPS (anastomose portossistêmica intra-hepática transjugular

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    Machado Márcio Martins

    2004-01-01

    Full Text Available A anastomose portossistêmica intra-hepática transjugular (TIPS compreende a técnica mais recente e mais popular para o alívio da hipertensão portal sintomática, especialmente para os casos com varizes e hemorragia digestiva alta, e menos comumente para o tratamento da ascite refratária. Os TIPS podem apresentar complicações após sua colocação, como as estenoses e oclusões. A ultra-sonografia e o Doppler permitem o estudo dos TIPS de uma forma não invasiva. Neste artigo os autores relatam os achados recentes à ultra-sonografia e ao Doppler nos casos de funcionamento normal e anormal (estenoses/oclusões dos TIPS.

  5. Validação da curva normal de peso fetal estimado pela ultra-sonografia para o diagnóstico do peso neonatal Validity of the normal fetal weight curve estimated by ultrasound for diagnosis of neonatal weight

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    José Guilherme Cecatti

    2003-02-01

    Full Text Available OBJETIVO: avaliar a concordância entre o peso fetal estimado (PFE por ultra-sonografia e o neonatal, o desempenho da curva normal de PFE por idade gestacional no diagnóstico de desvios do peso fetal/neonatal e fatores associados. MÉTODOS: participaram do estudo 186 grávidas atendidas de novembro de 1998 a janeiro de 2000, com avaliação ultra-sonográfica até 3 dias antes do parto, determinação do PFE e do índice de líquido amniótico e parto na instituição. O PFE foi calculado e classificado de acordo com a curva de valores normais de PFE em: pequeno para a idade gestacional (PIG, adequado para a idade gestacional (AIG e grande para a idade gestacional (GIG. A mesma classificação foi feita para o peso neonatal. A variabilidade das medidas e o grau de correlação linear entre o PFE e o peso neonatal foram calculados, bem como a sensibilidade, especificidade e valores preditivos para o uso da curva de valores normais de PFE para o diagnóstico dos desvios do peso neonatal. RESULTADOS: diferença entre o PFE e o peso neonatal variou entre -540 e +594 g, com média de +47,1 g, e as duas medidas apresentaram um coeficiente de correlação linear de 0,94. A curva normal de PFE teve sensibilidade de 100% e especificidade de 90,5% em detectar PIG ao nascimento, e de 94,4 e 92,8%, respectivamente, em detectar GIG, porém os valores preditivos positivos foram baixos para ambos. CONCLUSÕES: a estimativa ultra-sonográfica do peso fetal foi concordante com o peso neonatal, superestimando-o em apenas cerca de 47 g e a curva do PFE teve bom desempenho no rastreamento diagnóstico de recém-nascidos PIG e GIG.PURPOSE: tocompare the ultrasound estimation of fetal weight (EFW with neonatal weight and to evaluate the performance of the normal EFW curve according to gestational age for the diagnosis of fetal/neonatal weight deviation and associated factors. METHODS: one hundred and eighty-six pregnant women who delivered at the institution from

  6. Ultra-sonografia transcraniana em cães com distúrbios neurológicos de origem central Transcranial ultrasonography in dogs with central neurologycal disorders

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    C.F. Carvalho

    2007-12-01

    Full Text Available Avaliaram-se 55 cães com distúrbios neurológicos e verificou-se a ocorrência de afecções neurológicas de origem central, detectadas pela ultra-sonografia transcraniana (USTC. Vinte e nove (52,9% animais apresentaram diagnóstico compatível com hidrocefalia, e destes, 16 (55,1% eram fêmeas e 15 (51,7% tinham menos de dois anos. Quinze (27,3% cães apresentaram lesões focais, quatro (7,2%, alterações difusas e quatro (7,2% apresentavam imagens sugestivas de lissencefalia; em três (5,4% não foram detectadas alterações pela USTC. A hidrocefalia foi o distúrbio neurológico de origem central mais freqüente e a USTC é uma alternativa viável para auxiliar na rotina clínica veterinária como ferramenta diagnóstica na detecção de alterações morfológicas e estruturais do cérebro no cão.In this work, 55 dogs with neurologycal disorder were examined and central neurological affections were detected by transcranial ultrasonography (TCUS. They were classifyed in hydrocephaly, lissencephaly, focal and difuse parenchimal disorders, and none changes. From the examinated dogs, 52.9% presented diagnosis compatible with hydrocephaly, being 55.1% female and 51.7% younger than 2 year-old. Fifteen dogs (27.3% presented focal lesions, 7.2% diffuse lesions, 7.2% images that suggested lissencephaly, and in 5.4% no changes were detected by TCUS. It was concluded that hydrocephaly was the most frequent central neurologycal disorder and TCUS is a valuable alternative to be used in clinical routine as a tool of diagnostic to detect morphological and structural cerebral disorders in dogs.

  7. Imaging of foreign bodies in the face and ultrasound guided surgical removal; Diagnostico por imagem de corpos estranhos da face e retirada cirurgica guiada por ultra-sonografia

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    Lima, Claudio Marcio Amaral de Oliveira; Gambin, Moises; Ribeiro, Erica Barreiros; Amarante Junior, Jose Luiz de Medeiros [Hospital Naval Marcilio Dias, Rio de Janeiro, RJ (Brazil)]. E-mail: cmaol@br.inter.net; cmaolima@hotmail.com; Monteiro, Alexandra Maria Vieira [Pontificia Univ. Catolica do Rio de Janeiro (PUC/Rio), RJ (Brazil). Curso de Pos-Graduacao em Radiologia

    2006-10-15

    The identification and surgical removal of foreign bodies is a complex procedure in medical practice, principally when the involved material is radiolucent. The technological advent of the ultrasonography equipment comes enlarging the field of application of this method more and more, in medical practice. The authors describe a case of an ultrasound guided surgical removal of glass fragments from the face of a patient. The foreign bodies were previously diagnosed by ultrasound and computed tomography. The guided technic showed secure, less invasive and efficient, allowing the retreat of all the fragments. (author)

  8. Ultra-sonografia de características lineares e estimativas do volume de rins de cães Ultrasonographic measurement of linear characteristics and renal volumetry in dogs

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    K.M.O.R. Sampaio

    2002-06-01

    Full Text Available Obtiveram-se as medidas lineares de rins de cães adultos, clinicamente normais, por meio da ultra-sonografia, e estimou-se o volume dos rins de 35 cães (18 fêmeas e 17 machos sem raça definida e com idade entre dois e seis anos. Os animais foram divididos em três grupos de acordo com o peso corporal (3,1 a 10,0 kg; 10,1 a 20,0 kg e 20,1 a 45,0 kg. Os planos de secção sagital, dorsal e transversal foram utilizados para obtenção das medidas lineares de comprimento (C, largura (L e espessura (E. O volume renal foi calculado a partir das medidas lineares utilizando-se a fórmula para o volume de um elipsóide. Os valores médios encontrados para os três grupos foram, respectivamente: comprimento (4,73; 6,09 e 7,13cm, largura (2,81; 3,44 e 3,95cm, espessura (2,43; 3,00 e 3,58cm e volume (17,98; 33,36 e 53,81cm³. As dimensões dos rins esquerdo e direito e de machos e fêmeas foram equivalentes. Observaram-se correlações positivas entre todas as medidas renais e peso corporal.This work aimed to measure by ultrasonography the length, width and depth and to estimate the volume of kidneys of normal adult dogs. Thirty five dogs (18 females and 17 males of mixed breeds, aging from two to six years, were used. The animals were separated in three groups according to their body weights (3.1 to 10.0 kg; 10.1 to 20.0 kg and 20.1 to 45 kg. Sagittal, dorsal and transverse plans of section were used to obtain measures of length, width and depth. The kidney volume was estimated from these measures. Mean values according to the groups were, respectively: 4.73; 6.09 and 7.13cm for length; 2.81; 3.44 and 3.95cm for width; 2.43; 3.00 and 3.58cm for depth; and the estimated volumes were 17.98; 33.36 and 53.81cm³. The length, width, depth and volume of the left and right kidneys were similar, and no difference between male and female was found for these traits. Body weight of animals was positively correlated with all the kidney traits.

  9. Estimativa do Peso Fetal: Comparação Entre um Método Clínico e a Ultra-Sonografia Estimation of Fetal Weight: Comparison Between a Clinical Method and Ultrasonography

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    Alexandre Faisal Cury

    1998-12-01

    Full Text Available Objetivo: avaliar a validade da estimativa do peso fetal por método baseado na altura uterina - regra de Johnson. Métodos: foram estudadas 101 gestantes e seus recém-nascidos (RN, estimando-se o peso fetal pela utilização da regra de Johnson adaptada, que consiste em aplicação clínica de modelo matemático para cálculo do peso fetal baseado na altura uterina e na altura da apresentação fetal. O peso estimado foi obtido no dia do parto e foi comparado com o peso observado ao nascer, que constituiu o controle da análise da validade do método empregado. Na mesma data foi realizada ultra-sonografia obstétrica (US detalhada, que inclui cálculo do peso fetal pela aplicação das tabelas de Sheppard, e este peso, estimado pela US, foi comparado ao peso observado ao nascer. Resultados: os resultados destas comparações mostraram que a estimativa clínica empregada nesta casuística tem valor semelhante à US para avaliação do peso ao nascer: a margem de acerto do método clínico com variações de 5%, 10% e 15% entre peso estimado e peso observado foi de 55,3%, 73% e 86,7% respectivamente, e, para o US, de 60,7%, 75,4% e 91,1%, respectivamente. Conclusões:quando comparados, estes valores não se mostraram diferentes do ponto de vista estatístico, permitindo concluir-se que a avaliação clínica mostra acurácia semelhante à da US para o cálculo do peso ao nascer.Purpose: to assess the validity of fetal weight estimation by a method based on uterine height -- Johnson's rule. Methods: one hundred and one pregnant women and their newborn children were studied. The fetal weight was estimated using an adaptation of Johnson's rule, which consists of the clinical application of a mathematical model to calculate the fetal weight based on the uterine height and the height of fetal presentation. The estimated weight was obtained on the day of delivery and was compared to the weight observed after birth. This, in turn, was the control of

  10. Leukokoria in childhood: differential diagnosis using ultrasonography, computed tomography, and magnetic resonance imaging; Leucocoria na infancia: diagnostico diferencial por ultra-sonografia, tomografia computadorizada e ressonancia magnetica

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    Montandon Junior, Marcelo Eustaquio; Montandon, Cristiano [Colegio Brasileiro de Radiologia e Diagnostico por Imagem (CBR), Sao Paulo, SP (Brazil)]. E-mail: marmontandon@hotmail.com; Figueiredo, Sizenildo da Silva; Ribeiro, Flavia Aparecida de Souza; Nobrega, Bruno Barcelos da; Lobo, Leonardo Valadares Barbosa; Teixeira, Kim-Ir-Sen Santos [Goias Univ., Goiania (Brazil). Hospital das Clinicas. Servico de Diagnostico por Imagem e Anatomia Patologica; Jacob, Beatriz Mahmud [Goias Univ., Goiania (Brazil). Faculdade de Medicina. Radiologia e Diagnostico por Imagem

    2004-04-01

    Leukokoria is an abnormal pupillary reflex most commonly seen in children that usually results from an intra-ocular abnormality. The evaluation of a child with leukokoria should be performed particularly to rule out a retinoblastoma (the cause of leukokoria in half of the cases). The authors present the main clinical and imaging features for the diagnosis of the most common causes of leukokoria. (author)

  11. Ultrasonography as a predicting tool for carcass traits of young bulls Ultra-sonografia para predição das características da carcaça de bovinos jovens em confinamento

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    Liliane Suguisawa

    2003-12-01

    Full Text Available Considerable resources have been allocated to support research in the development of non-invasive and non-destructive techniques for carcass composition and quality evaluation. Ultrasonography is a reliable and relatively low-cost technique that can be used. In the present study, real-time ultrasonography was used to predict ribeye area (REA and subcutaneous fat thickness (FT in live animals as compared to carcass measurements. Animals used were 115 yearling bull calves (initial body weight, 329 kg, kept under feedlot conditions, of four genetic groups (30, ½ Angus x Nellore; 30, ½ Canchim x Nellore; 30, ½ Simmental x Nellore, and 25 Nellore, and two finishing frame sizes (small and large. Four ultrasonographic measurements were taken every 28 days until slaughter. Predictive precision of ultrasonographic measurements increased as animals approached slaughter, reaching maximum values at the last measurement (R²=0.68 and 0.82 for REA and FT, respectively. FT carcass measurements was influenced by genetic group and live measurements (P O desenvolvimento de técnicas não invasivas e não destrutivas para a avaliação da composição e qualidade de carcaça em animais tem mobilizado consideráveis recursos em pesquisa. A ultra-sonografia aparece neste contexto como uma técnica viável, confiável e de custo aceitável para esta função. No presente trabalho foi avaliada a técnica de ultra-sonografia em tempo real como ferramenta para predição da área de olho-de-lombo (AOL e espessura da camada de gordura subcutânea (ECG a partir de imagens tomadas em animais vivos, quando comparadas com as medições na carcaça. Foram utilizados 115 bovinos jovens (30, ½ Angus x Nellore; 30, ½ Canchim x Nellore; 30, ½ Simental x Nellore, e 25 Nellores, com peso inicial médio de 329 kg e de dois tamanhos à maturidade (pequeno e grande, no sistema de produção do novilho superprecoce. As medidas de ultra-sonografia foram realizadas a cada 28 dias

  12. Importância da ultra-sonografia ocular na avaliação pré-operatória de pacientes com catarata total The importance of ocular ultrasonography in the preoperative evaluation of patients with mature cataract

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    Álvaro Pedroso de Carvalho Lupinacci

    2004-02-01

    Full Text Available Com os avanços da cirurgia para catarata, o prognóstico da recuperação da visão aumentou drasticamente, tornando-se necessário prever resultados indesejados para a acuidade visual no pós-operatório. OBJETIVOS: Verificar a importância da ultra-sonografia ocular na avaliação pré-operatória do segmento posterior em pacientes com catarata madura, e relacionar possíveis doenças que possam comprometer os resultados cirúrgicos, sua prevalência e seus principais fatores de risco. MÉTODOS: Foi realizado estudo retrospectivo do prontuário de 262 pacientes em que houve a necessidade de ultra-sonografia ocular devido à presença de catarata madura, impedindo assim a avaliação fundoscópica do segmento posterior. Também foi avaliada a relação entre a presença dessas alterações e o sexo, idade, raça, história de trauma ocular, doenças sistêmicas e oculares e presença de catarata no olho contralateral. RESULTADOS: Encontraram-se alterações ecográficas em 24,8% dos exames realizados entre 1996 e 2001, dos quais o descolamento de retina (9,9% e as condensações vítreas (9,9% foram as mais comuns. CONCLUSÕES: Dentre os fatores de risco levantados como predisponentes para achados de ultra-sonografia ocular, a uveíte foi o único elemento estatisticamente significante. Não foi possível, pelos dados obtidos, correlacionar positivamente o trauma ocu-lar às patologias de segmento posterior descritas.With the new techniques of cataract surgery visual success has increased and it became necessary to foresee undesirable postoperative results regarding visual acuity. PURPOSE: To verify the role of ocular ultrasonography in the preoperative evaluation of patients with mature cataract searching for pos terior segment pathologies that may affect surgical results, their prevalence and the main associated risk factors. METHODS: A retrospective study was performed analyzing records of 262 patients indicated for ocular ultrasonography

  13. Effect of intertrochanteric osteotomy on the proximal femur of rabbits: assessment with power Doppler sonography and scintigraphy Efeito da osteotomia intertrocantérica no femur proximal de coelhos: avaliação com utra-sonografia power Doppler e cintilografia

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    Andrea S. Doria

    2007-01-01

    area unit.OBJETIVO: Regeneração em casos de lesão óssea resulta em aumento da vascularização local e remodelamento da medula óssea adjacente. A caracterização imagenológica de padrões vasculares e metabólicos no fêmur proximal após uma osteotomia intertrocantérica pode auxiliar ortopedistas a decidirem qual a terapêutica mais apropriada. O objetivo deste estudo foi avaliar as alterações temporais observadas por ultra-sonografia Doppler e cintilografia no fêmur proximal após a realização de uma osteotomia intertrocantérica; e comparar achados imagenológicos e histomorfométricos no estágio pós-operatório tardio (6 semanas após a cirurgia num modelo animal de lesão óssea. MATERIAIS AND MÉTODOS: Ambos os quadris de 12 coelhos adultos foram examinados por ultra-sonografia power Doppler e cintilografia antes e após (7 dias e 6 semanas uma osteotomia unilateral. A acurácia dos métodos de imagem foi avaliada usando-se o status operatório dos quadris and os resultados histomorfométricos (área vascular fracional e número de vasos/unidade de área como medidas de referência. RESULTADOS: Uma diferença significativa foi observada entre o número médio de pixels presentes no fêmur proximal operado e não-operado ao exame de power Doppler obtido no estágio pós-operatório tardio (P=0.049. Embora ser atingir significância estatística, a área abaixo da curva ("area-under-the-curve" dos exames de power Doppler (AUC=0.99 for numericamente superior à área abaixo da curva dos exames de cintilografia (AUC= 0.857±0.099 (P=0.15 para diferenciar fêmures proximais com relação a suas áreas vasculares fracionais no estágio pós-operatório tardio. Ao contrário, a cintilografia tendeu a apresentar uma "performance" diagnóstica superior (AUC=0.984±0.022 em relação ao Doppler (AUC=0.746±0.131 para demonstrar a quantidade de vasos por unidade de área (P=0.07 no estágio tardio. CONCLUSÃO: Nossos resultados despertam a importância de

  14. Calcinose peritendínea do tendão calcâneo associada a dermatomiosite: correlação entre radiografia convencional, ultra-sonografia, ressonância magnética e macroscopia cirúrgica

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    Rosa,Ana Cláudia Ferreira; Costa,Edegmar Nunes; Machado,Márcio Martins; Rocha,Válney Luiz da; Sernik,Renato Antônio; Nunes,Rodrigo Alvarenga; Lemes,Marcella Stival; Gomide,Lidyane Marques de Paula; Albieri,Alexandre Daher; Santos Júnior,Rubens Carneiro dos; Barros,Nestor de; Cerri,Giovanni Guido

    2006-01-01

    A calcinose intersticial é uma afecção incomum, na qual existe deposição de cálcio localizada ou disseminada na pele, tecido celular subcutâneo, músculos e tendões. Freqüentemente a calcinose está associada com doenças do tecido conjuntivo, como esclerodermia e dermatomiosite. Os autores relatam um caso de calcinose intersticial associada a dermatomiosite, estudada com radiografia convencional, ultra-sonografia, ressonância magnética, e com correlação com a macroscopia cirúrgica....

  15. Calcinose peritendínea do tendão calcâneo associada a dermatomiosite: correlação entre radiografia convencional, ultra-sonografia, ressonância magnética e macroscopia cirúrgica

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    Rosa Ana Cláudia Ferreira

    2006-01-01

    Full Text Available A calcinose intersticial é uma afecção incomum, na qual existe deposição de cálcio localizada ou disseminada na pele, tecido celular subcutâneo, músculos e tendões. Freqüentemente a calcinose está associada com doenças do tecido conjuntivo, como esclerodermia e dermatomiosite. Os autores relatam um caso de calcinose intersticial associada a dermatomiosite, estudada com radiografia convencional, ultra-sonografia, ressonância magnética, e com correlação com a macroscopia cirúrgica.

  16. Correlação entre o exame clínico, a mamografia e a ultra-sonografia com o exame anatomopatológico na determinação do tamanho tumoral no câncer de mama Correlation between clinical examination, mammography and ultrasonography with histopathological exam in the determination of tumor size in breast cancer

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    Fernanda Monteiro de Paula Siqueira

    2008-03-01

    Full Text Available OBJETIVO: avaliar qual o melhor método entre o exame clínico (EC, a mamografia (MMG e a ultra-sonografia (US na determinação pré-operatória do tamanho tumoral no câncer de mama, tendo como referência o exame anatomopatológico. MÉTODOS: foram incluídas neste estudo 184 pacientes com lesões mamárias detectadas por MMG e US, palpáveis ou não, e que foram submetidas a ressecção cirúrgica do tumor, com diagnóstico histopatológico de câncer de mama. O maior diâmetro tumoral foi avaliado por EC, MMG e US por um mesmo examinador, e a medida obtida por cada método foi correlacionada com o diâmetro máximo obtido pelo exame anatomopatológico. A análise comparativa foi feita por meio do coeficiente de correlação de Pearson (r. RESULTADOS: o coeficiente de correlação de Pearson encontrado entre o exame anatomopatológico e o EC foi 0,8; entre o exame anatomopatológico e a MMG foi 0,7 e entre o exame anatomopatológico e a US foi 0,7 (pPURPOSE: to evaluate which method is the best to determine pre-surgically the size of breast cancer: clinical examination, mammography or ultrasonography, using as a reference the anatomopathological exam. METHODS: this study has included 184 patients with palpable-or-not breast lesions, detected by mammography and ultrasonography, that were submitted to surgical resection of the tumor, with histopathological diagnosis of breast cancer. The same examiner evaluated clinically the largest tumoral diameter, through clinical examination, mammography and ultrasonography, and the measurements obtained by each method were correlated with the maximum diameter obtained by the anatomopathological exam. The comparative analysis has been done by Pearson's correlation coefficient (r. RESULTS: Pearson's correlation coefficient between the anatomopathological and the clinical exams was 0.8; between the anatomopathological exam and the mammography, 0.7; and between anatomopathological exam and ultrasonography 0

  17. Ultra-sonografia da aorta abdominal e de seus ramos em cães Ultrasonography of abdominal aorta and its branches in dogs

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    Lilian Kamikawa

    2007-04-01

    Full Text Available O ultra-som bidimensional e o ultra-som Doppler foram utilizados para avaliar a biometria e a hemodinâmica da aorta abdominal e artérias ilíacas externas de 131cães clinicamente normais. Os resultados da avaliação biométrica da aorta abdominal indicaram um diâmetro médio de 0,80cm para o seu segmento diafragmático (AOD; 0,74cm para o seu segmento caudal às artérias renais (AOR e 0,69cm para o segmento cranial à sua bifurcação (AOT. A artéria ilíaca externa direita (AIED apresentou o diâmetro médio de 0,42cm e a artéria ilíaca externa esquerda (AIEE o diâmetro médio de 0,39. O estudo hemodinâmico da aorta abdominal apresentou velocidade de pico sistólico médio de 104,00cm/s para AOR; 99,61cm/s para AOT; 85,47cm/s para AIED e 99,51cm/s para AIEE. Verificaram-se correlações de diferentes intensidades entre os diâmetros vasculares em diferentes pontos de tomadas e os fatores biométricos corpóreos (CRL. Correlações baixas foram observadas quando esses diâmetros foram confrontados com a idade.A duplex ultrasound system incorporating a pulsed wave Doppler ultrasound probe with conventional B-mode real-time imaging was used to evaluate the biometric and the hemodynamic of abdominal aorta and external iliac arteries of a hundred and thirty one normal dogs. Results of biometrics of abdominal aorta, presented a mean diameter of 0.80cm in its diaphragmatic segment (AOD; 0.74cm in its segment caudal to the renal arteries (AOR and 0.69cm in the segment cranial to its termination (AOT. The right-external-iliac artery (AIED presented a mean diameter of 0.42cm and the left-external iliac artery (AIEE a mean diameter of 0.39cm. The hemodynamic study of the abdominal aorta presented a medium systolic peak velocity to AOR of 104cm per sec.; to AOT of 99.61cm per sec.; to AIED of 85.47cm per sec. and to AIEE of 99.51cm per sec. Correlations of different intensities between the vascular diameters have been verified between the

  18. Estimativa do Peso Fetal: Comparação Entre um Método Clínico e a Ultra-Sonografia

    OpenAIRE

    Cury,Alexandre Faisal; Garcia,Sidney A. L.

    1998-01-01

    Objetivo: avaliar a validade da estimativa do peso fetal por método baseado na altura uterina - regra de Johnson. Métodos: foram estudadas 101 gestantes e seus recém-nascidos (RN), estimando-se o peso fetal pela utilização da regra de Johnson adaptada, que consiste em aplicação clínica de modelo matemático para cálculo do peso fetal baseado na altura uterina e na altura da apresentação fetal. O peso estimado foi obtido no dia do parto e foi comparado com o peso observado ao nascer, que consti...

  19. Relevância da ultra-sonografia dos tendões flexores em cavalos Puro Sangue de corrida na adaptação ao treinamento Significance of flexor tendon ultrasonography in training thoroughbred horses

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    Carolina Roxana Greig

    2005-08-01

    Full Text Available Vinte e quatro potros Puro Sangue de Corrida (PSC, com dois anos de idade foram avaliados ultra-sonograficamente, durante o período final da doma e início de treinamento, através da imagem transversal dos tendões flexor digital superficial (TFDS e profundo (TFDP. As avaliações foram realizadas com intervalos de 15 dias. A área transversal (AT, a textura dos ecos e a ecogenicidade dos tendões foram avaliadas nas sete zonas da região metacarpiana através de um programa de mensuração de imagens do próprio aparelho de ultra-sonografia. Durante a doma e treinamento, houve diminuição da AT na zona IA e IIIA (PThe cross-sectional area (CSA of the superficial digital flexor tendon (SDFT and deep digital flexor tendon (DDFT of twenty four thoroughbreds was ultrasonographically evaluated before and during their initial training to determine the effect of exercise on the tendon CSA, texture and echogenicity to characterize the response to training. Ultrasonographic transverse images of the left forelimb were obtained every fifteen days. The SDFT CSA of zones IA and IIIA showed a decrease (P<0.05, f=0.010 e f=0.023 res. during the breaking and training period and an increase (P< 0.05 of zone IIIC (f=0.039. Evaluating just the training period, SDFT CSA results of zones IA, IIIA and IIIC were similar. The DDFT showed no variation during the breaking phase but when the training phase was evaluated there was a decrease (P<0.05 in zones IA (f=0.006 and IIIA (f=0.006. Evaluating both breaking and training periods the DDFT showed a decrease (P<0.05 in zones IA (f=0.027, IIIA (f=0.0001 and IIIB (f=0.0031. Fiber texture and tendon echogenicity showed no significant difference between breaking and last reading during training. This study provides evidence of variation of adaptation among the ultrasonographic zones of both SDFT and DDFT to exercise during training of thoroughbred horses. Ultra-sonography is not the most indicated method to evaluate the

  20. Avaliação dos tumores hepáticos ao Doppler Doppler evaluation of liver tumors

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    Márcio Martins Machado

    2004-10-01

    Full Text Available Os avanços recentes na ultra-sonografia têm ampliado a possibilidade de detecção de tumores hepáticos. Isto tem auxiliado na perspectiva de melhora do prognóstico destes pacientes, à medida que novas técnicas terapêuticas têm surgido. Neste artigo os autores relatam achados ao Doppler que podem auxiliar na identificação e caracterização dos tumores hepáticos, avaliando dados do Doppler colorido, pulsado e do Doppler de amplitude ("power Doppler". Fazem, também, referência a novas modalidades de imagem, como o uso da harmônica.Recent advances in ultrasound have optimized the detection of liver tumors and helped to improve the prognosis of patients with this condition as newly developed and improved therapeutic modalities have been established. The authors review important Doppler findings which may help in the identification and characterization of some hepatic tumors through the evaluation of color Doppler, pulsed Doppler and power Doppler features. New imaging methods such as the use of harmonics imaging are also reviewed.

  1. Ultra-sonografia do fígado, aparelho renal e reprodutivo da jibóia (Boa constrictor Ultrasonography of the liver, renal and reproductive apparatus of Boa constrictor Snake

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    Francisco C. P. Neto

    2009-04-01

    Full Text Available Atualmente os animais silvestres têm despertado o interesse particular na criação domestica. Na medicina de animais selvagens, os exames ultra-sonográficos podem ser considerados como ferramenta para diagnosticar e prevenir doenças. Deste modo, realizou-se um estudo em 20 jibóias (Boa constrictor, a fim de caracterizar a morfologia e aparência ultra-sonográfica das estruturas presentes da cavidade celomática desses animais. Ultra-sonograficamente, o fígado apresentou-se variando de hipoecóica a levemente hiperecogênica, com margens ecogênicas e ecotextura homogênea em toda sua extensão. Os rins mostraram formato elipsóide, com cápsula fina, regular e hiperecóica. Os folículos ovarianos apresentaram formato ovóide, margens finas, regulares e discretamente hiperecóicas. As estruturas do sistema reprodutor do macho não foram evidenciadas com precisão, devido a sua ecogenicidade similar em relação às estruturas adjacentes e pela presença do "corpo gorduroso" localizado nessa região. A ultra-sonografia da cavidade celomática em jibóias demonstrou ser uma técnica rápida e de fácil acesso, permitindo identificar a morfologia, sintopia e aparência ultra-sonográfica de estruturas como o fígado, rins e de folículos vitelogênicos nas fêmeas.Currently, wild animals have been received special attention for domestic breeding. In Wild Animal Medicine, ultrasonographic exams could be considered as a tool to diagnose and prevent disease. Ultrasonographic examination of twenty snakes (Boa constrictor was performed in order to describe the morphological and ultrasonography appearance of their coelomic structures. Examination by ultrasonography revealed the parechymal liver ranging from slightly hypoechogenic to hyperechogenic, with echogenic margins and homogeneous echotexture in total scanning of this organ. The kidney was accessible for examination by sagittal ultrasound, showing an ellipsoid shape, a hyperechogenic capsule

  2. Volume do embrião estimado pela ultra-sonografia tridimensional entre a sétima e a décima semana de gestação Embryo volume estimated by three-dimensional ultrasonography at seven to ten weeks of pregnancy

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    João Bortoletti Filho

    2008-10-01

    Full Text Available OBJETIVO: avaliar a evolução do volume do embrião (VE entre a sétima e a décima semana de gestação por meio da ultra-sonografia tridimensional. MÉTODOS: realizou-se um estudo de corte transversal com 63 gestantes normais entre a sétima e a décima semana. Os exames ultra-sonográficos foram realizados por meio de um transdutor endocavitário volumétrico. Para o cálculo do VE, utilizou-se o método VOCAL (Virtual Organ Computer-aided Analysis com ângulo de rotação de 12º, com delimitação de 15 planos seqüenciais. Para o VE foram calculadas médias, medianas, desvios padrão e valores máximo e mínimo em todas as idades gestacionais. Para se avaliar a correlação entre o VE e o comprimento cabeça-nádega (CCN foi criado gráfico de dispersão, sendo o ajuste realizado pelo coeficiente de determinação (R². Para se determinarem intervalos de referência do VE em função do CCN, utilizou-se a seguinte fórmula: percentil =VE+K versus dp, com K=1,96. RESULTADOS: o CCN variou de 9,0 a 39,7 mm, com média de 23,9 mm (±7,9 mm, enquanto o VE variou de 0,1 a 7,6 cm³, com média de 2,7 cm³ (±3,2 cm³. O VE foi altamente correlacionado com o CCN, sendo que o melhor ajuste foi obtido com regressão quadrática (VE=0,165 - 0,055 x CCN + 0,005 x CCN²; R²=0,853. O VE médio variou de 0,1 (-0,3 a 0,5 cm³ a 6,7 cm³ (3,8 a 9,7 cm³ no intervalo de 9 a 40 mm do CCN. Neste intervalo o VE aumentou 67 vezes, enquanto o CCN aumentou apenas 4,4 vezes. CONCLUSÕES: o VE é um parâmetro mais sensível que o CCN para avaliar o crescimento embrionário entre a sétima e a décima semana de gestação.PURPOSE: to evaluate the embryo's volume (EV between the seventh and the tenth gestational week, through tridimensional ultrasonography. METHODS: a transversal study with 63 normal pregnant women between the seventh and the tenth gestational week. The ultrasonographical exams have been performed with a volumetric abdominal transducer. Virtual

  3. Hipertensão portal por esquistossomose mansônica hepatoesplênica: efeito da desconexão ázigo-portal com esplenectomia no diâmetro e na velocidade média de fluxo do sistema portal (estudo ultra-sonográfico com Doppler Hepatosplenic schistosomotic portal hypertension: effect of esophagogastric devascularization with splenectomy on the diameter and mean flow velocity in the portal system (ultra-sonographic Doppler study

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    Azzo WIDMAN

    2001-01-01

    Full Text Available Racional - A esplenectomia com desconexão ázigo-portal tem sido indicada para o tratamento da hemorragia digestiva pelas varizes esofágicas na hipertensão portal da esquistossomose mansônica hepatoesplênica. Todavia, esta técnica terapêutica apresenta índices variáveis de complicações trombóticas precoces do sistema portal (13,3% a 53,2%. Supondo que as alterações circulatórias devidas ao tratamento cirúrgico tenham papel preponderante neste acontecimento, procurou-se identificar elementos hemodinâmicos que, dentre os múltiplos fatores causais, tenham facilitado a ocorrência desta complicação. Com este intuito estudou-se comparativamente, mediante ultra-sonografia com Doppler, o sistema portal de dois grupos de pacientes em condições clínicas semelhantes: não-operados e com desconexão ázigo-portal em fase pós-operatória tardia (período superior a 6 meses. Casuística/Método - Foram estudados 58 pacientes com esquistossomose mansônica hepatoesplênica e com antecedentes de hemorragia digestiva alta, divididos em dois grupos: A (29 sob controle ambulatorial: clínico e endoscópico; B (29 submetidos previamente a desconexão ázigo-portal. Em todos foi feita a medida do diâmetro e da velocidade média de fluxo do sangue na veia porta e seus ramos direito e esquerdo, mediante ultra-sonografia com Doppler. Os resultados foram submetidos a análise univariada inter e intragrupo. Resultados - No grupo A (não-operados: a veia porta apresentou diâmetro maior do que o dos ramos direito e esquerdo e nestes esta medida foi semelhante (10,6 ± 2,9, 8,0 ± 1,8, 9,1 ± 2,6 cm; a velocidade média de fluxo na veia porta e nos ramos portais foi semelhante (15,62 ± 6,17, 14,92 ± 5,33, 16,12 ± 4,18 cm/seg. No grupo B (operados: houve diminuição de ambos os parâmetros na veia porta e seus ramos (8,8 ± 1,7, 5,2 ± 1,2, 7,5 ± 2,2 cm/12,53 ± 2,60, 8,86 ± 1,75, 9,60 ± 3,75 cm/seg. Conclusões - Houve redu

  4. Ultra-sonografia mamária: avaliação dos critérios ecográficos na diferenciação das lesões mamárias Breast ultrasound: evaluation of echographic criteria for differentiation of breast lesions

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    Maria Julia Gregorio Calas

    2007-02-01

    Full Text Available OBJETIVO: O câncer de mama é uma das causas mais importantes de mortalidade feminina. Na busca do diagnóstico cada vez mais precoce, a associação de métodos diagnósticos tem sido utilizada com êxito, tendo grande participação a ultra-sonografia mamária diagnóstica e intervencionista. Este trabalho tem como objetivos: identificar os critérios ecográficos mais relacionados com benignidade e malignidade e avaliar as propriedades das características ecográficas, verificando o seu poder de predição de malignidade. MATERIAIS E MÉTODOS: Os critérios morfológicos ecográficos utilizados nas descrições das imagens foram: forma, limites, contorno, ecogenicidade, ecotextura, ecotransmissão, orientação e sinais secundários. A validação foi buscada em 450 imagens ecográficas, comparadas aos resultados de seguimento ou de histopatologia de peça cirúrgica. RESULTADOS: Os principais critérios de benignidade foram: forma definida, contorno regular, limites precisos, lesões isoecóicas ao tecido adiposo, ecotextura homogênea e orientação horizontal. Os critérios mais característicos de malignidade foram: forma indefinida, contorno irregular, limites parcialmente precisos e lesões hipoecóicas. O contorno irregular apresentou a maior sensibilidade (92,7% e o maior valor preditivo negativo (98,2% para malignidade, a orientação vertical apresentou a maior especificidade (99,3%, e a forma indefinida, o maior valor preditivo positivo (91,0%. CONCLUSÃO: O método padronizado para a caracterização e descrição das imagens ultra-sonográficas mamárias apresentado resultou em uniformidade e otimização dos laudos, viabilizando as condutas mais adequadas.OBJECTIVE: Breast cancer is one of the most important causes of death in women. The association of different diagnostic methods has been successfully employed as a means to enhance early diagnosis. In this scenario, the interventional and diagnostic breast ultrasound has

  5. Considerações sobre eficiência administrativa relacionado aos exames de ultra-sonografia, tomografia computadorizada e ressonância magnética nas afecções orbitárias Reasons for the administrative efficiency related to ultrassonography, computed tomography and magnetic resonance imaging tests in orbital diseases

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    Magno Watanabe

    2007-12-01

    Full Text Available OBJETIVOS: Enfocar os exames de ultra-sonografia (US, tomografia computadorizada (TC e ressonância magnética (RM, levantando, revisando e discutindo as seguintes medidas na melhoria da eficiência destes procedimentos na órbita: 1- Defasagem dos honorários médicos; 2- Vantagens e desvantagens dos exames; 3- Diretrizes clínicas. MÉTODOS: No período de julho de 2002 a março de 2003, realizou-se um levantamento dos valores dos exames orbitários de US, TC e RM pagos pelo Sistema Único de Saúde - SUS, operadoras de planos e seguros de saúde e particulares cobrados em três clínicas oftalmológicas e três clínicas radiológicas referenciadas. Pesquisa bibliográfica e revisão na literatura dos referidos exames e suas diretrizes clínicas nas afecções orbitárias. RESULTADOS: 1- Valores dos exames em reais (R$: US: 9,05 - SUS / 81,77 - AMB 90 / 57,01 - AMB/CIEFAS 93 / 102,00 - AMB/LPM 99 / 158,33 - particular. TC: 86,76 - SUS / 193,70 - AMB 90 / 196,30 - AMB/CIEFAS 93 / 204,12 - AMB/LPM 99 / 255,33 - particular. RM: 268,75 - SUS / 475,80 - AMB 90 e AMB/CIEFAS 93 / 472,50 - AMB/LPM 99 / 563,33 - particular; 2- Vantagens e desvantagens dos exames descritos de acordo com a revisão da literatura; 3- As doenças da órbita não têm ainda listadas suas diretrizes. CONCLUSÃO: Estes exames são os mais utilizados e consagrados pela sua eficácia no estudo da órbita. Para uma maior eficiência, devemos considerar as seguintes recomendações administrativas: 1- Modernização e atualização das tabelas de honorários com índices mínimos e mais justos na remuneração dos exames com reembolso dos insumos utilizados como filmes radiológicos e contrastes: 2- Promover e estimular a educação médica continuada, evitando o excesso de exames desnecessários ou inapropriados: 3- Elaboração e implementação de diretrizes e protocolos clínicos baseados em evidências nas principais doenças orbitárias que possam ser utilizados como refer

  6. Desempenho da ultra-sonografia na detecção das metástases em linfonodos axilares em mulheres com câncer de mama Performance of ultrasound in the detection of axillary lymph node metastases in breast cancer patients

    Directory of Open Access Journals (Sweden)

    Rodrigo Menezes Jales

    2005-09-01

    Full Text Available OBJETIVOS: avaliar o desempenho de diversas características ultra-sonográficas morfológicas (12 e doplervelocimétricas (7, para detecção de metástases linfonodais em mulheres com câncer de mama. MÉTODOS: foram incluídas 179 mulheres (181 axilas, entre janeiro e dezembro de 2004. Os exames ultra-sonográficos foram realizados com transdutor linear em tempo real (Toshiba-Power Vision-6000 (modelo SSA-370A. Para o estudo de parâmetros morfológicos foram utilizadas freqüências entre 7,5 e 12 MHz. Para os parâmetros Doppler foi utilizada freqüência de 5 MHz. Subsequentemente, as pacientes foram submetidas a axilectomia dos níveis I, II e III (158 ou à técnica do linfonodo sentinela (23. Foram calculadas a sensibilidade, a especificidade e os valores preditivos positivo e negativo para cada parâmetro. Para a associação de parâmetros foi utilizada a árvore de decisão. Foram estabelecidos os valores de corte para as variáveis contínuas por meio da curva ROC. RESULTADOS: ao exame ultra-sonográfico foi identificado pelo menos um linfonodo axilar em 173 (96% exames. O exame histológico detectou metástase linfonodal em 87 mulheres (48%. As melhores sensibilidades dos critérios morfológicos foram encontradas com o volume (62%, diâmetro ântero-posterior (62% e local do centro ecogênico (56%. Embora a especificidade da invasão da gordura adjacente (100%, regularidade das margens (92% e da ecotextura do parênquima (99% tenham sido elevadas, a sensibilidade destes parâmetros foi muito baixa. Nenhum critério dopplervelocimétrico alcançou 50% de sensibilidade. A árvore de decisão selecionou a localização do centro ecogênico, a ecotextura do parênquima e a regularidade das margens como melhor associação de parâmetros. CONCLUSÃO: o estadiamento dos linfonodos axilares por método não invasivo ainda é um objetivo não alcançado no tratamento das pacientes com câncer de mama.PURPOSE: to evaluate the role of

  7. Velocimetria Doppler no período neonatal em recém-nascidos a termo pequenos para idade gestacional Neonatal Doppler velocimetry in full term small-for-gestational age newborns

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    Iracema Augusta Carvalho Cortez Muniz

    2003-09-01

    Full Text Available Este estudo teve como objetivo avaliar o fluxo sanguíneo cerebral em recém-nascidos a termo pequenos para idade gestacional, utilizando ultra-sonografia Doppler craniana ao nascimento. O estudo foi desenvolvido no CAISM/UNICAMP (Centro de Saúde Terciário para Mulheres. Foram selecionados sessenta recém-nascidos e divididos em 2 grupos: 36 adequados para idade gestacional (AIG e 24 pequenos para idade gestacional (PIG. Foi realizada a avaliação de ultra-sonografia Doppler craniana nos grupos, entre 24-48 horas após o nascimento. A velocidade de fluxo sanguíneo cerebral foi menor no grupo PIG na artéria cerebral anterior (ACA. As medidas Doppler foram estatisticamente diferentes entre os grupos apenas para valores relacionados à velocidade de fluxo de pico sistólico (VFPS e velocidade de fluxo médio (VFM na ACA. Não houve diferenças significantes para nenhum dos parâmetros avaliados de velocidade de fluxo na artéria cerebral média (ACM. Concluiu-se que recém-nascidos PIG apresentaram VFPS e VFM significativamente menores apenas na ACA. A adequação peso/idade gestacional, presença de policitemia neonatal e valores de pressão arterial média estiveram estatisticamente associados a VFM na ACA. A presença de sofrimento fetal, valores de pressão arterial média e hábito de fumar durante a gestação estiveram estatisticamente associados a VFM na ACM.This study aimed to evaluate the cerebral blood flow of full term small-for-gestational age newborns, using cranial ultrasound Doppler at birth. This study was performed at CAISM/UNICAMP (Tertiary Health Center for Women. Sixty term newborns were selected and divided in two groups: appropriate-for-gestational age (AGA (36 neonates and small-for-gestational age (SGA (24 neonates. Cranial ultrasound Doppler evaluation was performed on both groups, between 24 and 48 hours after birth. Cerebral blood flow velocity (CBFV was lower in the small-for-gestational age group, in the anterior

  8. Tratamento da síndrome de Budd-Chiari por meio da colocação de tips e de "stent" venoso supra-hepático Transjugular intrahepatic portosystemic shunt (TIPS and suprahepatic venous stenting in the management of Budd-Chiari syndrome

    Directory of Open Access Journals (Sweden)

    Jurandi A. Bettio

    2002-11-01

    Full Text Available OBJETIVOS: Descrever o uso do "shunt" intra-hepático portossistêmico (TIPS e do "stent" venoso supra-hepático no manejo da síndrome de Budd-Chiari, enfocando suas indicações, aspectos técnicos e benefícios do procedimento. MATERIAIS E MÉTODOS: De janeiro de 1999 a março de 2002, nove casos de síndrome de Budd-Chiari foram encaminhados ao Serviço de Hemodinâmica do Hospital São Lucas, Porto Alegre, RS. A obstrução venosa supra-hepática foi constatada em todos os casos por meio de ultra-sonografia com Doppler em cores. A criação de TIPS foi realizada entre o sistema venoso supra-hepático ou a veia cava inferior e a veia porta, posicionando-se a endoprótese entre as duas abordagens. Doppler em cores pós-procedimento foi efetuado em todos os pacientes em períodos seriados. RESULTADOS: Três casos foram tratados inicialmente com inserção de "stent" venoso por apresentarem estenose preponderante em veias supra-hepáticas. Em dois desses casos ocorreu trombose do "stent", sendo necessária colocação de TIPS. Os demais seis casos foram tratados primariamente com TIPS. Dos oito "shunts" criados, trombose da endoprótese foi constatada em três casos, resolvidas com limpeza dos trombos e dilatação com balão em um caso e inserção de novas próteses nos demais. Embolização com molas de colaterais venosas ectasiadas foi efetuada em um paciente. CONCLUSÕES: A colocação de TIPS constitui-se numa estratégia terapêutica segura e efetiva na síndrome de Budd-Chiari, promovendo uma significativa melhora clínica e hemodinâmica dos pacientes, evitando procedimentos mais invasivos e podendo, em casos sem cirrose estabelecida, servir de tratamento definitivo da hipertensão portal.OBJECTIVE: To evaluate the use of transjugular intrahepatic portosystemic shunt (TIPS and suprahepatic venous stenting in the management of Budd-Chiari syndrome, emphasizing the indications, technical aspects and the advantages of the procedure

  9. Predictive values of Bi-Rads categories 3, 4 and 5 in non-palpable breast masses evaluated by mammography, ultrasound and magnetic resonance imaging; Valores preditivos das categorias 3, 4 e 5 do sistema Bi-Rads em lesoes mamarias nodulares nao-palpaveis avaliadas por mamografia, ultra-sonografia e ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Roveda Junior, Decio; Fleury, Eduardo de Castro Faria [Santa Casa de Misericordia de Sao Paulo, SP (Brazil). Faculdade de Ciencias Medicas. Servico de Diagnostico por Imagem]. E-mail: decio.jr@uol.com.br; Piato, Sebastiao [Santa Casa de Misericordia de Sao Paulo, SP (Brazil). Dept. de Obstetricia e Ginecologia. Clinica Ginecologica; Oliveira, Vilmar Marques de [Santa Casa de Misericordia de Sao Paulo, SP (Brazil). Dept. de Obstetricia e Ginecologia. Ginecologia Geral; Rinaldi, Jose Francisco [Santa Casa de Misericordia de Sao Paulo, SP (Brazil). Dept. de Obstetricia e Ginecologia. Clinica de Mastologia; Ferreira, Carlos Alberto Pecci [Santa Casa de Misericordia de Sao Paulo, SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Clinica Medica. Servico de Imagenologia Mamaria

    2007-03-15

    Objective: To evaluate the predictive value of BI-RADS{sup TM} categories 3, 4 and 5 in non-palpable breast masses assessed by mammography, ultrasound and magnetic resonance imaging. Materials And Methods: Twenty-nine patients with BI-RADS categories 3, 4 and 5 non-palpable breast masses identified by mammograms were submitted to complementary ultrasound and magnetic resonance imaging studies, besides excisional biopsy. In total, 30 biopsies were performed. The lesions as well as their respective BI-RADS classification into 3, 4 and 5 were correlated with the histopathological results. The predictive values calculation was made by means of specific mathematical equations. Results: Negative predictive values for category 3 were: mammography, 69.23%; ultrasound, 70.58%; and magnetic resonance imaging, 100%. Positive predictive values for category 4 were: mammography, 63.63%; ultrasound, 50%; and magnetic resonance imaging, 30.76%. For category 5, positive predictive values were: mammography and ultrasound, 100%; and magnetic resonance imaging, 92.85%. Conclusion: For category 3, the negative predictive value of magnetic resonance imaging was high, and for categories 4 and 5, the positive predictive values of the three modalities were moderate. (author)

  10. Doppler-guided hemorrhoidal artery ligation in the management of symptomatic hemorrhoids Ligadura de las arterias hemorroidales guiada por Doppler en el tratamiento de las hemorroides sintomáticas

    Directory of Open Access Journals (Sweden)

    J. M. Ramírez

    2005-02-01

    la intervención. Resultados: el tiempo medio de intervención fue de 27 (rango 18-43 minutos, localizando de media 5 (rango 4-7 ramas arteriales. No existieron complicaciones intraoperatorias. Ningún paciente presentó dolor severo o moderado en alguno de los controles, refiriendo habitualmente molestias anales discretas. La rectorragia autolimitada y el tenesmo fueron las complicaciones post-operatorias más frecuentes. Tras el seguimiento a 1 año, 19 enfermos estaban asintomáticos y en 6 ocasiones los síntomas habían disminuido significativamente, en el resto la intervención fue ineficaz. Agrupados los pacientes por grados, la técnica presentó malos resultados en sólo 3 pacientes con hemorroides grado III, pero en hemorroides grado IV, los resultados fueron malos en 4 de los 5 pacientes. Conclusiones: la ligadura de la arteria hemorroidal guiada por Doppler es una técnica sencilla, bien tolerada, con buenos resultados en hemorroides grado III.

  11. Ecocardiografia por Doppler tecidual no diagnóstico de rejeição após transplante cardíaco

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    Marcos Valério Coimbra Resende

    2011-07-01

    Full Text Available FUNDAMENTO: A biópsia endomiocárdica (BEM é o método padrão-ouro para o diagnóstico de rejeição celular (RC após transplante cardíaco (TC. OBJETIVO: Testar a hipótese de que o exame de imagem por Doppler tecidual (IDT pode detectar RC > 3A e agregar informação diagnóstica, comparado ao Doppler convencional. MÉTODOS: Cinquenta e quatro pacientes com TC foram submetidos à BEM e estudo ecocardiográfico através de IDT em até 24 horas. Comparamos os pacientes com TC e RC > 3A com pacientes com TC e RC 3A em 39/129 (30,2% das BEM. O melhor preditor isolado para o diagnóstico de RC foi a a'LAT, com sensibilidade de 76,3%, especificidade de 73,8% (p = 0,001. Na análise multivariada, a a'LAT (p = 0,001, a'SEP (p = 0,002, relação e'/a' LAT (p = 0,006, relação e'Mitral/ e'LAT (p = 0,014, SINF (p = 0,009 foram preditores de RC > 3A. Obtivemos um escore com sensibilidade de 88,2%, acurácia de 79,6%, e valor preditivo negativo de 92,9% para diagnosticar RC > 3A. O Doppler convencional (fluxo mitral e pulmonar venoso não foi relevante para predizer a RC > 3A. CONCLUSÃO: O estudo de IDT agregou informação diagnóstica para predizer RC > 3A quando comparado ao Doppler convencional. O modelo baseado em IDT pode ser tornar um método em potencial para detectar RC > 3A após TC.

  12. Ecocardiografia por Doppler tecidual no diagnóstico de rejeição após transplante cardíaco Ecocardiografía con Doppler tisular en el diagnóstico de rechazo después de transplante cardíaco Tissue doppler echocardiography in the diagnosis of heart transplantation rejection

    Directory of Open Access Journals (Sweden)

    Marcos Valério Coimbra Resende

    2011-07-01

    Full Text Available FUNDAMENTO: A biópsia endomiocárdica (BEM é o método padrão-ouro para o diagnóstico de rejeição celular (RC após transplante cardíaco (TC. OBJETIVO: Testar a hipótese de que o exame de imagem por Doppler tecidual (IDT pode detectar RC > 3A e agregar informação diagnóstica, comparado ao Doppler convencional. MÉTODOS: Cinquenta e quatro pacientes com TC foram submetidos à BEM e estudo ecocardiográfico através de IDT em até 24 horas. Comparamos os pacientes com TC e RC > 3A com pacientes com TC e RC 3A em 39/129 (30,2% das BEM. O melhor preditor isolado para o diagnóstico de RC foi a a'LAT, com sensibilidade de 76,3%, especificidade de 73,8% (p = 0,001. Na análise multivariada, a a'LAT (p = 0,001, a'SEP (p = 0,002, relação e'/a' LAT (p = 0,006, relação e'Mitral/ e'LAT (p = 0,014, SINF (p = 0,009 foram preditores de RC > 3A. Obtivemos um escore com sensibilidade de 88,2%, acurácia de 79,6%, e valor preditivo negativo de 92,9% para diagnosticar RC > 3A. O Doppler convencional (fluxo mitral e pulmonar venoso não foi relevante para predizer a RC > 3A. CONCLUSÃO: O estudo de IDT agregou informação diagnóstica para predizer RC > 3A quando comparado ao Doppler convencional. O modelo baseado em IDT pode ser tornar um método em potencial para detectar RC > 3A após TC.FUNDAMENTO: La biopsia endomiocárdica (BEM es el método gold standard para el diagnóstico de rechazo celular (RC después de transplante cardíaco (TC. OBJETIVO: Testear la hipótesis de que el examen de imagen con Doppler tisular (IDT puede detectar RC > 3A y agregar información diagnóstica, comparado al Doppler convencional. MÉTODOS: Cincuenta y cuatro pacientes con TC fueron sometidos a BEM y estudio ecocardiográfico a través de IDT en hasta 24 horas. Comparamos los pacientes con TC y RC > 3A con pacientes con TC y RC 3A en 39/129 (30,2% de las BEM. El mejor predictor aislado para el diagnóstico de RC fue la a'LAT, con sensibilidad de 76

  13. Utilidad del índice de resistencia obtenido por ultrasonido Doppler en nódulos tiroideos de características ecográficas malignas.

    Science.gov (United States)

    Butrón-García, Ángel Fernando; Méndez-García, Mario

    2018-01-01

    La patología nodular tiroidea tiene alta prevalencia en la población general. Su diagnóstico se ha incrementado con el Doppler, con el cual se pueden detectar características sugerentes de malignidad, como elevación de los índices de resistencia y pulsatilidad. Evaluar la correlación de un índice de resistencia alto y los hallazgos histopatológicos en pacientes con sospecha ecográfica de nódulos tiroideos malignos. Estudio prospectivo, observacional, transversal y analítico de pruebas diagnósticas, en el Hospital de Especialidades 25, Monterrey, Nuevo León. Se incluyó a pacientes con nódulos tiroideos de características ecográficas malignas; se obtuvo el índice de resistencia de los nódulos, que se comparó con los hallazgos histopatológicos. Se incluyeron 48 pacientes con diagnóstico ecográfico de nódulo tiroideo maligno. La correlación de índices de resistencia elevados y diagnóstico histopatológico de nódulos tiroideos malignos fue significativa (p = 0.001). La sensibilidad fue de 73.3 %, y la especificidad de 78.7 %; valor predictivo positivo de 61.1 % y valor predictivo positivo negativo de 86.6 %. La determinación del índice de resistencia cada vez es más empleada, pero la sensibilidad y especificidad es baja y no es un método confiable, por lo que aún se requieren otros métodos complementarios. Thyroid nodular disease is highly prevalent in the general population. Its diagnosis has increased with Doppler ultrasound, by means of which features suggestive of malignancy can be detected, such as resistance and pulsatility indices elevation. To assess the correlation of a high resistance index and histopathological findings in patients with ultrasonographic suspicion of malignant thyroid nodules. Prospective, cross-sectional, analytic, observational study of diagnostic tests carried out at Specialty Hospital 25, in Monterrey, Nuevo León. Patients with thyroid nodules of ultrasonographic malignant characteristics were included

  14. Mismatch paciente-prótesis aórtica. Comparación alejada por eco-Doppler transtorácico versus el estimado en el preoperatorio

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    Gabriel Converso

    2008-01-01

    Full Text Available Introducción:El mismatch paciente-prótesis (MPP aórtica se asocia con peor evolución posoperatoria.La utilización del área del orificio aórtico efectivo (AOE para cada tipo de prótesis, indexado por la superficie corporal (SC en el momento quirúrgico, puede permitir la elección de un tamaño de prótesis adecuado para cada paciente y así evitar el MPP.ObjetivoComparar la estimación de MPP por las AOE tabuladas con la diagnosticada en el posoperatorio alejado por eco-Doppler.Material y métodosSe analizaron retrospectivamente 57 pacientes, 43 hombres, con prótesis aórtica, operados más de 6 meses antes del estudio. Se calculó la SC del parte quirúrgico y el AOE indexada tabulada, el AOE posquirúrgica con eco-Doppler transtorácico por la ecuación de continuidad y se comparó el MPP prequirúrgico y posquirúrgico. Se consideró MPP aórtico un AOE indexada < 0,75 cm2/m2.ResultadosSe observó una prevalencia de MPP preoperatorio del 29,8% y posoperatorio del 54,4% (p = 0,029, con el 31% de MMP grave. La prevalencia de sobrepeso en la muestra estudiada fue del 80%.ConclusionesEn este grupo de pacientes con alta prevalencia de sobrepeso, la estimación del AOE preoperatoria indexada por SC de cada tipo de prótesis para predecir el MPP posoperatorio mostró diferencias significativas entre el diagnóstico del MPP estimado en el preoperatorio y el calculado por eco-Doppler en el posoperatorio. En futuros estudios es necesaria la inclusión de un grupo poblacional mayor, así como la revisión del método de cálculo del área valvular (p. ej., del tracto de salida del ventrículo izquierdo.

  15. Fatores maternos associados ao peso fetal estimado pela ultra-sonografia

    OpenAIRE

    Melo,Adriana Suely de Oliveira; Amorim,Melania Maria Ramos de; Assunção,Paula Lisiane; Melo,Fabiana de Oliveira; Gondim,Sheila Sherezaide Rocha; Carvalho,Danielle Franklin de; Cardoso,Maria Aparecida Alves

    2008-01-01

    OBJETIVO: avaliar o efeito de variáveis maternas, socioeconômicas e obstétricas, assim como a presença de incisuras na 20ª e na 24ª semana, sobre o peso fetal estimado no final da gravidez (36ª semana) em gestantes atendidas pelo Programa Saúde da Família em uma cidade do interior do Nordeste do Brasil. MÉTODOS: estudo longitudinal incluindo 137 gestantes. As gestantes foram acompanhadas a cada quatro semanas para aferição das condições clínicas, socioeconômicas e obstétricas, incluindo o pes...

  16. Doppler Tomography

    Science.gov (United States)

    Marsh, T. R.

    I review the method of Doppler tomography which translates binary-star line profiles taken at a series of orbital phases into a distribution of emission over the binary. I begin with a discussion of the basic principles behind Doppler tomography, including a comparison of the relative merits of maximum entropy regularisation versus filtered back-projection for implementing the inversion. Following this I discuss the issue of noise in Doppler images and possible methods for coping with it. Then I move on to look at the results of Doppler Tomography applied to cataclysmic variable stars. Outstanding successes to date are the discovery of two-arm spiral shocks in cataclysmic variable accretion discs and the probing of the stream/magnetospheric interaction in magnetic cataclysmic variable stars. Doppler tomography has also told us much about the stream/disc interaction in non-magnetic systems and the irradiation of the secondary star in all systems. The latter indirectly reveals such effects as shadowing by the accretion disc or stream. I discuss all of these and finish with some musings on possible future directions for the method. At the end I include a tabulation of Doppler maps published in refereed journals.

  17. Mapeamento da safena interna com ecocolor Doppler no pré-operatório de cirurgia de revascularização mioc��rdica

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    BARROS Fanilda Souto

    1999-01-01

    Full Text Available INTRODUÇÃO: O advento do ecocolor Doppler vascular tornou possível informar o estado anatômico e funcional da safena interna ao cirurgião cardiovascular, no pré-operatório da cirurgia de revascularização miocárdica, sem riscos para o paciente ou para o conduto venoso. O objetivo do estudo foi, juntamente com o cirurgião, avaliar a utilidade do mapeamento da safena interna no pré-operatório. CASUÍSTICA E MÉTODOS: Foram estudados, entre março de 1995 e maio de 1998, 208 extremidades inferiores de 104 pacientes selecionados para cirurgia de revascularização miocárdica. O critério utilizado para a seleção da safena foi a safena patente e o diâmetro maior ou igual a 3,0 mm, utilizando os aparelhos de ultra-sonografia ATL - HDI 3000 e Acuson-Sequóia 512. RESULTADOS: Dentre as 208 extremidades estudadas, 186 (89,4% das safenas preenchiam os critérios e a análise do cirurgião estava de acordo com a descrição do ecocolor Doppler. Dezessete (8,2% não preenchiam os critérios e, em 5 (2,4% ,o exame foi compatível com safenectomia radical. Das 17 safenas consideradas não apropriadas, 2 foram exploradas cirurgicamente, sendo a análise do cirurgião concordante com o ultra-som. CONCLUSÃO: Os autores concluem que o ecocolor Doppler, sendo um método diagnóstico não invasivo, pode ser útil no mapeamento da safena interna no pré-operatório de revascularização miocárdica devido à sua capacidade de identificar e selecionar com segurança o vaso a ser utilizado como conduto vascular, o que permite ao cirurgião cardíaco o planejamento cirúrgico.

  18. Tamizaje y prevención de pre-eclampsia guiado por Doppler de arterias uterinas: revisión sistemática de la literatura

    OpenAIRE

    Sáez O, Nicolás; Carvajal C, Jorge

    2012-01-01

    Antecedentes: La pre-eclampsia (PE) es una enfermedad grave asociada al embarazo con una prevalencia de ~3%. La identificación de las mujeres en riesgo podría mejorar el resultado materno y perinatal. La estimación de riesgo individual de PE permitiría ofrecer un tratamiento preventivo para ésta [ej: aspirina (AAS)]. Se ha descrito el Doppler de arterias uterinas (DAUt) en primer y segundo trimestre como un método de tamizaje de PE. Objetivo: Recopilar la evidencia disponible sobre el uso del...

  19. He-Ne laser effects on blood microcirculation. An in vivo study through laser doppler flowmetry; Efeito do laser de helio neonio sobre a microcirculacao sanguinea durante a reparacao tecidual. Estudo in vivo por meio de fluxometria laser doppler

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, Silvia Cristina

    2002-07-01

    Blood microcirculation performs an important function in tissue repair process, as well as in pain control, allowing for greater oxygenation of the tissues and the accelerated expulsion of metabolic products, that may be contributing to pain. Low Intensity Laser Therapy (LILT) is widely used to promote healing, and there is an assumption that it is mechanism of action may be due to an enhancement of blood supply. The purpose of this study was to evaluate, using laser Doppler flowmetry (LDF), the stated effects caused by radiation emitted by a He-Ne laser ({lambda}=632.8 nm) on blood microcirculation during tissue repair. To this end, 15 male mice were selected and received a liquid nitrogen provoked lesion, above the dorsal region, and blood flow was measured periodically, during 21 days. Due to radiation emission by the LDF equipment, a control group was established to evaluate possible effects caused by this radiation on microcirculation. To evaluate the He-Ne laser effects, a 1.15 J/cm{sup 2} dose was utilized, with an intensity of 6 mW/cm{sup 2}. The results obtained demonstrate flow alterations, provoked by the lesion, and subsequent inflammatory response. There was no statistical difference between the studied groups. As per the analysis of the results there is no immediate effect due the radiation emitted by a He Ne laser on microcirculation, although a percentage increase was observed in day 7 on medium blood flow rate in irradiated specimens. New studies are necessary to validate the use of this wavelength, in order to promote beneficial alterations in blood supply in radiated areas. (author)

  20. Valor preditivo do resultado fetal da dopplervelocimetria de ducto venoso entre a 11ª e a 14ª semanas de gestação Predictive value for fetal outcome of Doppler velocimetry of the ductus venosus between the 11th and the 14th gestation week

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Gollo

    2008-01-01

    Full Text Available OBJETIVO: estudar o valor da dopplervelocimetria do ducto venoso (DV entre a 11º e a 14º semanas de gestação, associado à medida da translucência nucal (TN, na detecção de resultado fetal adverso. MÉTODOS: foram estudados 1.268 fetos consecutivamente. Em 56 casos, realizou-se estudo citogenético no material obtido, por meio de biópsia de vilosidade coriônica e, em 1.181 casos, o resultado teve como base o fenótipo do recém-nascido. Todos os fetos foram submetidos, além da ultra-sonografia de rotina, à medida da TN e à dopplervelocimetria do DV. Trata-se de um estudo transversal e prospectivo. Foram calculados e analisados, para fins de prevalência e índices de acurácia: sensibilidade, especificidade, valor preditivo positivo (VPP, valor preditivo negativo (VPN, probabilidade de falso-positivo (PFP, probabilidade de falso-negativo (PFN, razão de probabilidade positiva e razão de probabilidade negativa. RESULTADOS: do total de 1.268 fetos, foram selecionados para análise 1.183 casos. Deste total, 1.170 fetos eram normais (98,9% e 13 fetos tiveram resultado fetal adverso ao nascimento (1,1% - incluindo morte fetal (trissomia 21 e 22 em dois casos, síndrome genética (Nooman em um caso, fetos polimalformados em dois casos, cardiopatia em três casos e outros defeitos estruturais em cinco casos. A prevalência do DV alterado (onda A zero/reversa na população estudada foi de 14 casos (1,2%, com taxa de falso-positivo de 0,7%. CONCLUSÕES: há correlação significativa entre alteração da dopplervelocimetria do DV e a medida da TN, como marcadores ultra-sonográficos de primeiro trimestre, na detecção de resultado fetal adverso, especialmente para malformações graves. O Doppler do DV foi capaz de diminuir o resultado falso-positivo, comparativamente ao uso isolado da TN, melhorando consideravelmente o VPP do teste.PURPOSE: to study the value of Doppler velocimetry of the ductus venosus, between the 11th and 14th weeks of

  1. Persistência hiperplástica do vítreo primitivo: avaliação por métodos de imagem

    Directory of Open Access Journals (Sweden)

    Jacob Beatriz Mahmud

    2003-01-01

    Full Text Available Persistência hiperplásica do vítreo primitivo (PHVP é um desenvolvimento anormal, afetando crianças, resultante da falha de regressão do vítreo primitivo e dos vasos hialóides, com proliferação de tecido conectivo. A PHVP pode ter três variações: uma anterior, outra posterior e uma terceira com a combinação das duas. Clinicamente manifesta-se como leucocoria (reflexo branco pupilar em um olho de dimensões reduzidas. Esta anomalia é usualmente unilateral e não associada com outros achados sistêmicos. Leucocoria, descolamento de retina, pregas retinianas e catarata podem confundir PHVP com outras afecções oculares que têm achados semelhantes. Retinoblastoma, catarata congênita, retinopatia da prematuridade e pseudogliomas são doenças com achados semelhantes aos da PHVP. A visualização direta dos remanescentes do sistema vascular hialóide fetal é a melhor evidência da lesão presente, se não fosse, muitas vezes impossivel, à fundoscopia, devido à opacidade do tecido. Nestes casos, a visualização indireta, por meio de ultra-sonografia, tomografia computadorizada e ressonância magnética, fornece o diagnóstico. As imagens obtidas por estes métodos proporcionam, ainda, informações e diagnóstico diferencial com outras doenças, particularmente com o retinoblastoma. Os autores fazem uma revisão na literatura e apresentam um estudo iconográfico das imagens e achados da PHVP.

  2. Vascularização uterina de éguas prenhes de jumento e de garanhão monitoradas por ultrassonografia Doppler

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    Sabina G.C. Lemos

    Full Text Available RESUMO: Este estudo teve como objetivo analisar e descrever os achados ultrassonográficos do útero de éguas gestantes de diferentes idades, de jumento e garanhão, utilizando a técnica de ultrassonografia Doppler Espectral, visando caracterizar os índices de resistência (RI e pulsatilidade (PI até 154 dias de gestação. Foram utilizadas 20 éguas em idade reprodutiva, sem raça definida. As avaliações foram realizadas nas artérias uterinas. Não foi constatada interação entre os valores de RI e PI obtidos nos cornos uterinos (que iniciaram ou não a gestação com o tempo da gestação (P>0,05, desta forma os dados foram discutidos separadamente. Não foram encontradas diferenças entre as avaliações de RI e PI quando comparado os cornos que iniciaram ou não a gestação (P>0,05. Verificou-se efeito de tempo (P0,05. As éguas gestantes de jumento apresentaram maior vascularização uterina no corno não gestante, que as éguas gestantes do garanhão. Com exceção do RI no lado não gravídico, foi verificado efeito de idade da fêmea sobre o lado da gestação (P<0,05, onde as éguas idosas, tanto no corno que iniciou a gestação e o contralateral, tiveram PI e RI mais altos, ou seja, menos vascularizados. Concluiu-se que a vascularização uterina não apresentou diferença entre os cornos uterinos. Há um aumento da vascularização uterina no 70º dia de gestação. Éguas gestantes de jumentos apresentaram maior vascularização uterina, quando comparada às éguas gestantes de garanhões. Éguas com idade acima de 15 anos apresentaram menor vascularização uterina, quando comparadas com idade inferior a 15 anos.

  3. Avaliação do bem-estar fetal pela dopplervelocimetria com mapeamento em cores Evaluation of fetal well-being through color doppler velocimetry

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    Cleide Mara Mazzotti de Oliveira Franzin

    1999-01-01

    Full Text Available Objetivos: Avaliar a eficiência do exame dopplervelocimétrico no diagnóstico do bem-estar fetal. Metodologia: Foram analisadas 130 gestantes atendidas no Serviço de Ultra-Sonografia do Centro de Atenção Integral à Saúde da Mulher da Universidade Estadual de Campinas, entre a 28ª e a 42ª semana. Foram feitas correlações entre o Doppler das artérias umbilical, cerebral média e aorta abdominal fetal com os resultados perinatais adversos. As gestantes selecionadas para o estudo foram submetidas eletivamente ao parto cesáreo, no máximo quatro horas após o exame Doppler. Considerou-se como resultados perinatais adversos: índice de Apgar ao 5º minuto menor que sete, internação em unidade de terapia intensiva neonatal, retardo de crescimento intra-uterino, sofrimento fetal agudo, mortalidade perinatal, hipoglicemia, enterocolite necrosante e hemorragia cerebral. Os índices de impedância das artérias umbilical, cerebral média e aorta abdominal foram relacionados caso a caso com os resultados perinatais adversos. Resultados: a relação sístole/diástole da artéria umbilical apresentou maior sensibilidade (80,76% do que o índice de pulsatilidade e índice de resistência da artéria umbilical. O estudo Doppler da artéria umbilical apresentou melhor sensibilidade que o da artéria cerebral média e da aorta abdominal na detecção de resultados perinatais adversos. Conclusão: a dopplervelocimetria das artérias umbilical e cerebral média apresentou boa capacidade de avaliação do bem-estar fetal e associação significativa com resultados perinatais adversos.Purpose: to evaluate the accuracy of Doppler velocimetry in the diagnosis of fetal well-being. Methods: a total of 130 pregnant women assisted at the Ultrasound Unit of the Center for Integral Assistance of Women's Health, UNICAMP, between the 28th and 42nd gestational weeks was analyzed. The correlation between fetal umbilical and middle cerebral arteries, abdominal

  4. Desarterialização transanal guiada por doppler associada ao reparo anorretal na doença hemorroidária: a técnica do THD Transanal desarterialization guided by Doppler associated to anorectal repair in hemorrhoids: THD technic

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    Carlos Walter Sobrado-Junior

    2012-12-01

    Full Text Available INTRODUÇÃO: O tratamento cirúrgico para hemorroidas deve ter indicação individual e baseia-se no sintoma predominante (sangramento ou prolapso, na gravidade da doença e na presença ou ausência de componente externo (plicoma. Cabe ao cirurgião conhecer as mais variadas técnicas para que possa encontrar o tratamento mais adequado caso a caso. TÉCNICA: O procedimento THD consiste na ligadura alta seletiva e guiada por Doppler de até seis ramos arteriais submucosos que irrigam as hemorroidas, levando à sua desarterialização, associada à correção do prolapso (reparo anorretal ou lifting. Utiliza equipamento e kit especiais. CONCLUSÃO: A técnica do THD tem mostrado bons resultados iniciais. Por ser técnica cirúrgica em que se respeita a anatomia, ela age diretamente sobre a fisiopatologia da afecção e corrige suas principais consequências, ela parece bastante promissora. Sua aplicação inicial pode ser nos pacientes com doença hemorroidária de II grau, que tenham indicação de tratamento cirúrgico, e de III e IV graus, nestes últimos, podendo ser associada à ressecção de plicomas.INTRODUCTION: Surgical treatment for hemorrhoids should be indicated individually and is based on the predominant symptom (bleeding or prolapse, severity of disease and the presence or absence of external component (plicoma. Surgeons must choose among varied techniques the one suitable for each case. TECHNIC: The THD procedure consists of Doppler guided high ligation, selective to up six submucosal arterial branches that supply the hemorrhoids, leading to its desarterialization associated with prolapse repair (anorectal repair or lifting. It uses special equipment and kit. CONCLUSION: THD technique has shown good initial results. Because surgical technique respects the anatomy, it acts directly on the pathophysiology of the disease and corrects its principal consequences; it looks quite promising. Its initial application may be in patients

  5. Evaluation of pelvic varicose veins using color Doppler ultrasound: comparison of results obtained with ultrasound of the lower limbs, transvaginal ultrasound, and phlebography Avaliação de varizes pélvicas por Doppler colorido: comparação dos resultados obtidos com ultrassom dos membros inferiores, ultrassom transvaginal e flebografia

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    Fanilda Souto Barros

    2010-06-01

    étodos diagnósticos não-invasivos mais comumente usados para avaliar a insuficiência venosa pélvica, enquanto a flebografia ainda é considerada como o padrão-ouro. Objetivos: Determinar a prevalência de varizes dos membros inferiores originadas na pélvis em um grupo de pacientes do sexo feminino e determinar a concordância entre os resultados obtidos por Doppler colorido dos membros inferiores, ultrassom transvaginal e flebografia. Métodos: A AMOstra incluiu pacientes do sexo feminino encaminhadas para o laboratório vascular para triagem dos membros inferiores. As pacientes diagnosticadas com trombose venosa profunda foram excluídas. A análise dos dados incluiu o coeficiente de concordância kappa, o teste de McNemar e os valores de sensibilidade e especificidade. Resultados: De um total de 1.020 pacientes, 124 (12.2% tiveram achados compatíveis com refluxo de origem pélvica. Entre essas pacientes, 51 (41.2% eram casos recorrentes. Um total de 249 foram submetidas a ultrassom transvaginal. Houve concordância significativa entre os achados ultrassonográficos dos membros inferiores e os achados transvaginais. A flebografia foi realizada em 54 pacientes. A comparação entre o ultrassom transvaginal e a flebografia foi associada a 96.2% de sensibilidade e 100% de especificidade. Conclusões: OS AUTores chamam a atenção para a prevalência relativamente alta de varizes dos membros inferiores originadas na pélvis, sugerindo uma importante, embora subdiagnosticada, causa de varizes recorrentes.

  6. Carcass traits of surubim (“Pseudoplatystoma” spp. evaluated by ultrasound Rendimento de carcaça em surubim ("Pseudoplatystoma" spp. avaliado por ultra-som

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    Daniela Chemim Melo

    2008-12-01

    Full Text Available The parameters of carcass trait of alive surubim (Pseudoplatystoma spp. evaluated by ultrasound were estimated in this trial. A total of 34 fish was divided into two groups according to average body weight: group 1 = 2.7 kg e group 2 = 1.5 kg. The fish were measured for total, head and standard lengths. Ultrasound images of four defined points were obtained: 1 - anterior insertion of dorsal fin; 2 - posterior insertion of dorsal fin; 3 - anterior insertion of fat fin and 4 - insertion of caudal fin. After, weights of carcass, head, shank fillet and belly fillet were obtained. Correlations of measures obtained by the ultrasound images with carcass yield traits were determined. The point 3 showed the best correlations for yield of group 1 with: carcass (0.91, head (0.86, shank fillet (0.87 and belly fillet (0.91. Carcass yield of group 1 was higher (70.9% than group 2 (66.9%, probably due to the highest head weight of these animals. The best equations for carcass yield and fillet weight were the ones that considered the measures of point 3 and total length, respectively. Ultrasound for evaluation of carcass traits in alive surubim is a reliable technique, once it can maintains reproducers with great performance inside stock.Objetivou-se com este trabalho definir parâmetros de avaliação do rendimento de carcaça em surubins Pseudoplatystoma spp. vivos por intermédio da ultra-sonografia. Foram utilizados 34 peixes divididos em dois grupos conforme peso médio: grupo 1 = 2,7 kg e grupo 2 = 1,5 kg. De cada exemplar obtiveram-se as medidas de comprimento total, comprimento de cabeça e comprimento padrão. Foram realizadas imagens dorso ventrais em quatro pontos: 1 - base anterior da nadadeira dorsal; 2 - base posterior da nadadeira dorsal; 3 - base anterior da nadadeira adiposa e 4 - base do pedúnculo caudal, onde foram mensuradas altura, largura e área da musculatura epi-axial. Posteriormente, foram obtidos pesos da carcaça, da cabeça, do fil

  7. Experimental intoxication of pregnant goats with Tetrapterys multiglandulosa A. Juss. (Malpighiaceae Intoxicação experimental por Tetrapterys multiglandulosa A. Juss. (Malpighiaceae em cabras gestantes

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    M.M. Melo

    2001-02-01

    ês dias. Foi detectada por ultra-sonografia morte fetal e, ao exame clínico, presença de secreção vaginal com subseqüente aborto. Os animais dos grupos I e II (tradados abortaram no terceiro e no final do segundo mês de gestação, respectivamente, e juntos com os do grupo III (controle foram sacrificados e submetidos a exames anátomo-histopatológicos. Pela histopatologia observou-se placentite focal com grande quantidade de células trofoblásticas binucleadas em apoptose, além de endometrite focal aguda e petéquias vulvo-vaginais. Todos os fetos abortados estavam subdesenvolvidos quando comparados com os fetos do grupo III (controle devido à malnutrição, pois nenhum defeito congênito pôde ser notado. Vários fetos abortados mostravam alguma autólise, pois sua morte precedia em cinco e três dias o aborto, nos tratamentos I e II, respectivamente. As lesões fetais observadas foram hemorragias difusas ou focais na pele, meninges e serosa visceral.

  8. Pancreatic capillary blood flow during caerulein-induced pancreatitis evaluated by a laser-doppler flowmeter in rats Estudo das alterações do fluxo capilar pancreático após infusão de ceruleína avaliado por laser-Doppler em ratos

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    Roberto Ferreira Meirelles Jr.

    2003-01-01

    Full Text Available PURPOSE: The pancreatic capillary blood flow (PCBF was studied to determine its alterations during caerulein-induced pancreatitis in rats. METHODS: Twenty rats were divided in groups: control and caerulein. A laser-Doppler flowmeter to measure PCBF continuously was used. Blood pressure (BP and heart rate (HR were monitored. Serum biochemistry analyses were determined. Histopathological study was performed. RESULTS: The PCBF measured a mean of 109.08 ± 14.54% and 68.24 ± 10.47% in control group and caerulein group, respectively. Caerulein group had a mean decrease of 31.75 ± 16.79%. The serum amylase was 1323.70 ± 239.10U.I-1 and 2184.60 ± 700.46U.I-1 in control and caerulein groups, respectively. There was a significant difference in the PCBF (pOBJETIVO: O fluxo capilar pancreático (FCP foi estudado para determinar suas alterações durante a pancreatite aguda induzida por ceruleína, em ratos. MÉTODOS: Vinte ratos foram divididos em grupo controle e grupo ceruleína. Um laser-Doppler fluxímetro foi empregado para determinar, continuamente, o FCP durante 120 minutos. A pressão arterial média (PAM e a freqüência cardíaca (FC foram determinadas, durante o experimento. Análise bioquímica sérica e estudo histopatológico, por microscopia ótica, do tecido pancreático foram realizados, ao final do experimento. RESULTADOS: O FCP foi em média 109,08 ± 2,17% e 68,24 ± 16,79% nos grupos controle e ceruleína , respectivamente. No grupo ceruleína, houve uma diminuição média de 31,75 ± 16,79%. Os níveis de amilase sérica foram de 1323,70 ± 239,10U.I-1 e 2184,60 ± 700,46U.I-1 nos grupos controle e ceruleína, respectivamente. Houve diferença significante (p<0,05 no FCP e na amilasemia, quando comparado o grupo controle com o grupo ceruleína. Embora micro e macrovacuolização estivessem presentes no grupo ceruleína, não houve diferença histológica entre os grupos. CONCLUSÃO: A diminuição do FCP parece um evento precoce

  9. Evaluation of left ventricular diastolic echocardiographic parameters in healthy dogs by pulsed-wave Doppler Avaliação de parâmetros ecocardiográficos diastólicos do ventrículo esquerdo de cães saudáveis por meio de Doppler pulsátil

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    Guilherme G. Pereira

    2009-04-01

    Full Text Available Left ventricular diastolic dysfunction plays an important role on heart failure progression. In order to obtain additional reference values of left ventricular diastolic parameters and investigate influence of common variables, peak E wave (peak E, peak A wave (peak A, E/A ratio (E/A, E wave deceleration time (EDT and isovolumic relaxation time (IRVT were studied in 40 clinically healthy dogs, by pulsed wave Doppler. The following values were obtained: peak E = 0.747 ± 0.117 m/s, peak A = 0.487 ± 0.062 m/s, E/A = 1.533 ± 0.198, EDT = 88.7 ± 9.2 ms and IRVT = 0.080 ± 0.009 s. Some parameters were influenced by heart rate (peak E, peak A and IRVT, by age (peak A and E/A and by body weight (TRIV. Gender influence was absent. Values obtained can be used as reference for canine specimens but its interpretation should consider on the influence of related variables.A disfunção diastólica do ventrículo esquerdo contribui de maneira importante para a progressão da insuficiência cardíaca. No intuito de obter valores de referência adicionais para os parâmetros diastólicos do ventrículo esquerdo e para investigar a influência de variáveis comuns, estudou-se, por meio de Doppler pulsátil, a velocidade máxima da onda E (Vmáx.E, a velocidade máxima da onda A (Vmáx.: A, a relação E/A (E/A, o tempo de desaceleração da onda E (TDE e o tempo de relaxamento isovolumétrico (TRIV em 40 cães clinicamente saudáveis. Os seguintes valores foram obtidos: Vmáx.E = 0,747±0,117m/s, Vmáx.A = 0,487±0,062m/s, E/A = 1,533±0,198, TDE = 88,7±9,2ms e TRIV = 0,080±0,009s. Alguns parâmetros foram influenciados pela freqüência cardíaca (Vmáx.E, Vmáx.A e TRIV, pela idade (Vmáx.A e E/A e pelo peso corpóreo (TRIV. Não houve influência pelo sexo. Os valores obtidos podem ser utilizados como referência para a espécie canina, porém devem ser interpretados considerando-se a influência das variáveis descritas.

  10. Prevalência de hipertensão pulmonar avaliada por ecocardiografia Doppler em uma população de pacientes adolescentes e adultos com fibrose cística Prevalence of pulmonary hypertension evaluated by Doppler echocardiography in a population of adolescent and adult patients with cystic fibrosis

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    Paula Maria Eidt Rovedder

    2008-02-01

    Full Text Available OBJETIVO: Determinar a prevalência de hipertensão pulmonar (HP em pacientes com fibrose cística (FC, comparar características clínicas, escore radiológico, função pulmonar e parâmetros ecocardiográficos nos grupos com e sem HP e correlacionar achados ecocardiográficos com características clínicas, escore radiológico e função pulmonar. MÉTODOS: Estudo transversal prospectivo em pacientes clinicamente estáveis (idade > 16 anos atendidos por um programa de adultos para FC. Os pacientes foram submetidos a avaliação clínica, ecocardiografia Doppler, testes de função pulmonar e exame radiológico do tórax. RESULTADOS: Obteve-se a velocidade de regurgitação tricúspide (VRT em 37 dos 40 pacientes estudados. A prevalência de HP foi de 49% com um ponte de corte da VRT de 2,5 m/s (18 pacientes e de 30% com um ponte de corte da VRT de 2,8 m/s (11 pacientes. Os valores de saturação periférica de oxigênio (SpO2 em repouso, escore clínico, volume expiratório forçado no primeiro segundo (VEF1 e capacidade vital forçada (CVF foram significativamente menores no grupo com HP. A VRT correlacionou-se significativamente com SpO2 em repouso (p OBJECTIVE: To determine the prevalence of pulmonary hypertension (PH in patients with cystic fibrosis (CF, to compare clinical characteristics, radiographic scores, pulmonary function, and echocardiographic parameters in patients with and without PH, and to correlate echocardiographic findings with clinical characteristics, radiographic scores, and pulmonary function. METHODS: This was a prospective, cross-sectional study involving clinically stable patients (aged 16 or older enrolled in an adult CF program. The patients were submitted to clinical evaluation, Doppler echocardiography, pulmonary function tests, and chest X-rays. RESULTS: Tricuspid regurgitant jet velocity (TRV was obtained in 37 of the 40 patients studied. The prevalence of PH was 49% with a TRV cut-off of 2.5 m/s (18 patients

  11. Sub-Doppler spectroscopy

    International Nuclear Information System (INIS)

    Hansch, T.W.

    1983-01-01

    This chapter examines Doppler-free saturation spectroscopy, tunable cw sources, and Doppler-free two-photon spectroscopy. Discusses saturation spectroscopy; continuous wave saturation spectroscopy in the ultraviolet; and two-photon spectroscopy of atomic hydrogen 1S-2S. Focuses on Doppler-free laser spectroscopy of gaseous samples. Explains that in saturation spectroscopy, a monochromatic laser beam ''labels'' a group of atoms within a narrow range of axial velocities through excitation or optical pumping, and a Doppler-free spectrum of these selected atoms is observed with a second, counterpropagating beam. Notes that in two-photon spectroscopy it is possible to record Doppler-free spectra without any need for velocity selection by excitation with two counterpropagating laser beams whose first order Doppler shifts cancel

  12. Doppler flowmetry in preeclampsia.

    Science.gov (United States)

    Zahumensky, J

    2009-01-01

    The purpose of this study was to summarize the new published data on the Doppler flowmetry in preeclampsia. We summarize the new published data on the Doppler flowmetry in uteroplacental, fetoplacental and fetal circulation in preeclampsia. The present review summarized the results of clinical research on the Doppler flowmetry in the screening of risk of preclampsia, in the diagnosis of preclampsia and in the fetal risk in preclampsia (Ref. 19). Full Text (Free, PDF) www.bmj.sk.

  13. Avaliação da função endotelial em pacientes com esclerose sistêmica limitada por meio do eco Doppler da artéria braquial Evaluation of endothelial function in patients with limited systemic sclerosis by use of brachial artery Doppler ultrasound

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    Tatiana Melo Fernandes

    2012-08-01

    Full Text Available OBJETIVO: O objetivo deste estudo foi comparar a resposta dilatadora dependente e independente do endotélio em pacientes portadores de esclerose sistêmica limitada (ESL com aquela de indivíduos sadios de mesmo gênero, idade e cor. MÉTODOS: Vinte mulheres adultas, não obesas, não tabagistas, não diabéticas, não dislipidêmicas, não hipertensas, que preencheram os critérios para esclerose sistêmica (ES segundo o American College of Rheumatology, foram submetidas ao exame de Doppler de artéria braquial do membro superior direito. Foi analisada a resposta dilatadora, dependente do endotélio, após isquemia induzida com esfigmomanômetro por cinco minutos no braço direito, e a resposta dilatadora, independente do endotélio, após administração de 300 mcg de nitroglicerina (NTG sublingual. Esses resultados foram comparados com a resposta obtida em indivíduos sadios. RESULTADOS: O diâmetro longitudinal da artéria braquial (DAB foi significativamente menor na fase basal 1 nos pacientes com ESL (3,57 ± 0,52 mm e 3,93 ± 0,39 mm, respectivamente no grupo paciente (P e grupo-controle (C, P = 0,005. Não foi encontrada diferença estatisticamente significativa entre a velocidade das hemácias (VH após isquemia/hiperemia reativa (HR e após NTG (110,2 ± 43,86 cm/s vs. 102,0 ± 25,89 cm/s e 63,80 ± 17,69 cm/s vs. 65,4 ± 12,90 cm/s nos grupos P e C, após HR e NTG, respectivamente. Também não foi encontrada diferença significativa entre o DAB após HR e após NTG (3,77 ± 0,59 mm vs. 4,14 ± 0,49 mm e 4,44 ± 0,64 mm vs. 4,70 ± 0,58 mm nos grupos P e C, após HR e NTG, respectivamente. CONCLUSÃO: Embora o grupo de pacientes com ESL tenha apresentado menor DAB basal, a resposta dilatadora dependente e independente do endotélio se manteve preservada em ambos os grupos.OBJECTIVES: The aim of this study was to compare the brachial artery endothelium-dependent and endothelium-independent dilating responses in patients with limited

  14. Doppler ultrasound exam of an arm or leg

    Science.gov (United States)

    Peripheral vascular disease - Doppler; PVD - Doppler; PAD - Doppler; Blockage of leg arteries - Doppler; Intermittent claudication - Doppler; Arterial insufficiency of the legs - Doppler; Leg pain and ...

  15. Differential doppler heterodyning technique

    DEFF Research Database (Denmark)

    Lading, Lars

    1971-01-01

    Measuring velocity without disturbing the moving object is possible by use of the laser doppler heterodyning technique. Theoretical considerations on the doppler shift show that the antenna property of the photodetector can solve an apparent conflict between two different ways of calculating...

  16. Doppler ultrasound monitoring technology.

    Science.gov (United States)

    Docker, M F

    1993-03-01

    Developments in the signal processing of Doppler ultrasound used for the detection of fetal heart rate (FHR) have improved the operation of cardiotocographs. These developments are reviewed and the advantages and disadvantages of the various Doppler and signal processing methods are compared.

  17. The Cognitive Doppler.

    Science.gov (United States)

    Kozoil, Micah E.

    1989-01-01

    Discusses the learning needs of students in the concrete operational stage in mathematics. Identifies the phenomenon of reduced cognitive performance in an out-of-class environment as the "Cognitive Doppler." Suggests methods of reducing the pronounced effects of the Cognitive Doppler by capitalizing on the students' ability to memorize…

  18. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H.; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...... vectors. This review briefly introduces the principles behind colour Doppler imaging and describes some clinical applications. It then describes the basic components of conventional colour Doppler systems and the methods used to derive velocity information from the ultrasound signal. Next, a number of new...

  19. Invasão do nervo óptico por melanoma peripapilar: relato de caso Optic nerve invasion by juxtapapillary melanoma: case report

    Directory of Open Access Journals (Sweden)

    Eduardo Ferrari Marback

    2003-06-01

    Full Text Available Tumores pigmentados localizados sobre o disco óptico são raros e representam desafio diagnóstico. Paciente masculino, 60 anos, apresenta baixa da acuidade visual no olho esquerdo devido à lesão pigmentada que cobre o disco óptico. Foi indicada a enucleação com recusa pelo paciente. O quadro evoluiu com descolamento de retina. Examinado em outro serviço teve indicação de vitrectomia também recusada. Retorna aos nossos cuidados; feita a enucleação o diagnóstico anatomopatológico revelou melanoma maligno da coróide com invasão pós-laminar do nervo óptico. A importância prognóstica da invasão do nervo óptico por melanoma da coróide ainda não está totalmente esclarecida. Embora raro, tumor pigmentado cobrindo o nervo óptico pode representar melanoma maligno. O diagnóstico diferencial destes casos é geralmente difícil, porém seu reconhecimento à ultra-sonografia ocular é patente e descolamento de retina associado é sinal de atividade tumoral. Os riscos de disseminação da doença exigem atenção na suspeita diagnóstica e conduta precisa.Small-pigmented lesions over the optic disc are very rare and may represent a diagnostic challenge. To report a case of a small malignant choroidal melanoma invading the optic nerve. A 60-year-old male presents with low vision in the left eye due to a small, pigmented lesion over the optic disc. At first the patient refused enucleation. One month later, after further drop in visual acuity, the patient was seen at another service, diagnosed as having a retinal detachment, and pars plana vitrectomy was proposed but also refused by the patient. Returning to our service, the eye was enucleated and a final diagnosis of choroidal melanoma with post-laminar optic nerve invasion was made. Although rare, pigmented lesions over the optic disc may represent a malignant melanoma. The prognostic significance of optic nerve invasion by choroidal melanoma is not clear yet. The differential

  20. Doppler radar flowmeter

    Science.gov (United States)

    Petlevich, Walter J.; Sverdrup, Edward F.

    1978-01-01

    A Doppler radar flowmeter comprises a transceiver which produces an audio frequency output related to the Doppler shift in frequency between radio waves backscattered from particulate matter carried in a fluid and the radiated radio waves. A variable gain amplifier and low pass filter are provided for amplifying and filtering the transceiver output. A frequency counter having a variable triggering level is also provided to determine the magnitude of the Doppler shift. A calibration method is disclosed wherein the amplifier gain and frequency counter trigger level are adjusted to achieve plateaus in the output of the frequency counter and thereby allow calibration without the necessity of being able to visually observe the flow.

  1. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...

  2. Comparação dos valores de débito cardíaco obtidos por termodiluição e dopplerfluxometria transesofágica Comparison between two methods for hemodynamic measurement: thermodilution and oesophageal doppler

    Directory of Open Access Journals (Sweden)

    Roberto Manara Victorio Ferreira

    2007-08-01

    Full Text Available OBJETIVO: A termodiluição (TD é padrão de monitorização hemodinâmica. Alguns par��metros hemodinâmicos podem ser medidos através do Doppler Transesofágico (DTE. Método simples, menos invasivo. Com o objetivo de avaliar a acurácia do DTE foram comparados TD e DTE na determinação de medidas de débito cardíaco (DC. MÉTODOS: Foram determinadas 192 medidas simultâneas, em diferentes situações clínicas em dez pacientes com idade entre 21 85 anos (cinco do gênero masculino e cinco do feminino, oito internados sépticos em uso de drogas vasoativas e dois monitorizados para laringectomia e transplante hepático; todas avaliadas ao longo de quatro horas, em intervalos de 30 minutos. Foram utilizados dois tipos de doppler: o DeltexR, e o ArrowR, introduzidos entre 35 e 45 cm da fossa nasal e localizados no ponto de maior diâmetro da aorta descendente. Na TD, foi utilizado cateter de artéria pulmonar (Swan Ganz BaxterR e monitor DX-2001R, confirmado o posicionamento radiologicamente e através das curvas pressóricas geradas. As medidas do DC realizadas através da TD foram obtidas com soro fisiológico gelado, sendo considerada a média de quatro medidas não diferentes de 5%. Foi aplicado o método estatístico de Bland e Altman, com utilização de gráfico de regressão linear. RESULTADOS: Não houve diferença estatisticamente significante entre esses dois métodos de medida hemodinâmica, com coeficiente de correlação de 0,88 para o DC (Doppler DeltexR X Swan Ganz BaxterR e coeficiente de correlação de 0,99 DC (Doppler Arrow rR X Swan Ganz BaxterR respectivamente, observando-se correlação. CONCLUSÃO: A medida das variáveis hemodinâmicas ao DTE foi obtida com facilidade nos dez pacientes estudados e revelou ter este dispositivo acurácia compatível à TD.OBJECTIVES: Thermodilution (TD is the "gold standard method" for hemodynamic monitoring. Some parameters can be measured by Oesophageal Doppler (OD, which is

  3. Steerable Doppler transducer probes

    International Nuclear Information System (INIS)

    Fidel, H.F.; Greenwood, D.L.

    1986-01-01

    An ultrasonic diagnostic probe is described which is capable of performing ultrasonic imaging and Doppler measurement consisting of: a hollow case having an acoustic window which passes ultrasonic energy and including chamber means for containing fluid located within the hollow case and adjacent to a portion of the acoustic window; imaging transducer means, located in the hollow case and outside the fluid chamber means, and oriented to direct ultrasonic energy through the acoustic window toward an area which is to be imaged; Doppler transducer means, located in the hollow case within the fluid chamber means, and movably oriented to direct Doppler signals through the acoustic window toward the imaged area; means located within the fluid chamber means and externally controlled for controllably moving the Doppler transducer means to select one of a plurality of axes in the imaged area along which the Doppler signals are to be directed; and means, located external to the fluid chamber means and responsive to the means for moving, for providing an indication signal for identifying the selected axis

  4. The phenomenon of Doppler

    International Nuclear Information System (INIS)

    Stoll, I.; Seidlerova, I.; Schwippel, J.; Poss, O.; Solc, M.

    1992-01-01

    The book is devoted to the life and work of Christian Doppler and particularly to his links to Prague and to the Slovak town of Banska Stiavnica. Many historical facts concerning Doppler's activities as well as the history of physics and astronomy are collected. Information is also presented about the Czech Technical University, the Society of Czechoslovak Mathematicians and Physicists, the Czechoslovak Astronomical Society, the Czechoslovak Spectroscopic Society and the Czechoslovak Society for the History of Science and Technology. The publication is amply supplemented with historical pictorial material (M.D.). 92 figs., 82 refs

  5. Doppler radar physiological sensing

    CERN Document Server

    Lubecke, Victor M; Droitcour, Amy D; Park, Byung-Kwon; Singh, Aditya

    2016-01-01

    Presents a comprehensive description of the theory and practical implementation of Doppler radar-based physiological monitoring. This book includes an overview of current physiological monitoring techniques and explains the fundamental technology used in remote non-contact monitoring methods. Basic radio wave propagation and radar principles are introduced along with the fundamentals of physiological motion and measurement. Specific design and implementation considerations for physiological monitoring radar systems are then discussed in detail. The authors address current research and commercial development of Doppler radar based physiological monitoring for healthcare and other applications.

  6. Doppler ion program description

    International Nuclear Information System (INIS)

    Henline, P.

    1980-12-01

    The Doppler spectrometer is a conventional Czerny-Turner grating spectrometer with a 1024 channel multiple detector. Light is dispersed across the detector, and its output yields a spectrum covering approximately 200 A. The width of the spectral peak is directly proportional to the temperature of the emitting ions, and determination of the impurity ion temperature allows one to infer the plasma ion temperature. The Doppler ion software system developed at General Atomic uses a TRACOR Northern 1710-31 and an LSI-11/2. The exact configuration of Doublet III is different from TRACOR Northern systems at other facilities

  7. Pulse Doppler radar

    CERN Document Server

    Alabaster, Clive

    2012-01-01

    This book is a practitioner's guide to all aspects of pulse Doppler radar. It concentrates on airborne military radar systems since they are the most used, most complex, and most interesting of the pulse Doppler radars; however, ground-based and non-military systems are also included. It covers the fundamental science, signal processing, hardware issues, systems design and case studies of typical systems. It will be a useful resource for engineers of all types (hardware, software and systems), academics, post-graduate students, scientists in radar and radar electronic warfare sectors and milit

  8. Doppler evaluation of valvular stenosis

    International Nuclear Information System (INIS)

    Kisslo, J.; Krafchek, J.; Adams, D.; Mark, D.B.

    1986-01-01

    One of the reasons why use of Doppler echocardiography is growing rapidly is because of its utility in detecting the presence of valvular stenosis and in estimating its severity. Detection of the presence of stenotic valvular heart disease using Doppler echocardiography was originally described over 10 years ago. It has been demonstrated that Doppler blood velocity data could be used to estimate the severity of a stenotic lesion. This chapter discusses the evaluation of valvular stenois using Doppler

  9. Doppler-musical instrument

    International Nuclear Information System (INIS)

    Sato, T.J.; Watanabe, N.

    2001-01-01

    We propose a possible ultra-high energy resolution backscattering spectrometer optimized to spallation neutron source. A combination of multi monochromator crystal and Doppler drive provides considerable neutron flux, together with the reasonable energy range -30 < E < 30 μeV, even when the ultra-high energy resolution of ΔE∼0.03 μeV is attained. (author)

  10. Scanning laser Doppler vibrometry

    DEFF Research Database (Denmark)

    Brøns, Marie; Thomsen, Jon Juel

    With a Scanning Laser Doppler Vibrometer (SLDV) a vibrating surface is automatically scanned over predefined grid points, and data processed for displaying vibration properties like mode shapes, natural frequencies, damping ratios, and operational deflection shapes. Our SLDV – a PSV-500H from...

  11. Índice de congestão portal e a ocorrência de trombose portal pós-dape Portal congestion and thrombosis after EDS

    Directory of Open Access Journals (Sweden)

    Fabio Gonçalves Ferreira

    2005-08-01

    Full Text Available OBJETIVO: Comparar os dados obtidos pela ultra-sonografia com doppler no pré-operatório de esquistossomóticos submetidos à desconexão ázigo-portal com esplenectomia (DAPE, calculando o índice de congestão portal, e sua correlação com a trombose portal no pós-operatório. MÉTODOS: Foram estudados 65 pacientes submetidos à DAPE por hipertensão portal esquistossomótica com antecedente de hemorragia digestiva, divididos em dois grupos: Grupo A (28 pacientes que não desenvolveram trombose portal pós-operatória e Grupo B (37 pacientes com trombose portal no pós-operatório. Analisaram-se através de ultra-sonografia com doppler no pré-operatório os seguintes parâmetros da veia porta: diâmetro, área, velocidade média de fluxo do sangue, fluxo de sangue, e estabeleceu-se o índice de congestão portal. RESULTADOS: O diâmetro, área e o fluxo da veia porta foram maiores no grupo B (média de 1,52 cm; 1,77 cm² e 2533,12 ml/min em relação ao grupo A (média de 1,33 cm; 1,44 cm² e 1609,03 ml/min com p = 0,03; 0,03 e 0,04 respectivamente. O índice de congestão portal não foi estatisticamente significativo na comparação dos dois grupos (p = 0,07. CONCLUSÃO: O índice de congestão portal obtido no pré-operatório através da ultra-sonografia com doppler não se mostrou preditivo de trombose portal no pós-operatório dos doentes estudados.BACKGROUND: The study compared the preoperative portal vein congestion index estimated by Doppler ultrasound and the postoperative portal vein thrombosis of patients submitted to esophagogastric devascularization and splenectomy (EDS. METHODS: 65 patients with portal hypertension due to schistosomiasis and previous gastrointestinal bleeding submitted to EDS were divided into two groups: GROUP A (28 patients without postoperative portal vein thrombosis and GROUP B (37 patients with postoperative portal vein thrombosis. The following parameters of preoperative Doppler ultrasound of the

  12. Avaliação por imagem do comprometimento osteoarticular e de nervos periféricos na hanseníase Imaging methods evaluation in osteoarticular and peripheral nerves involvement in leprosy

    Directory of Open Access Journals (Sweden)

    Helena Lúcia Alves Pereira

    2006-06-01

    Full Text Available Na hanseníase, lesões ósseas por invasão direta do bacilo são de baixa incidência, e os achados radiológicos destas lesões são de osteomielite aguda ou crônica similares aos de outras infecções granulomatosas. As lesões ósseas mais comuns são devidas ao trauma e a infecção secundária nos tecidos denervados. Radiograficamente, são observados vários graus de reabsorção das extremidades distais envolvendo mãos e pés, ocasionando perda dos dígitos e osteoartropatia neuropática de pequenas articulações. Os achados radiológicos são semelhantes às outras condições nas quais há déficit sensorial, como esclerodermia, siringomielia e diabetes mellitus. A ultra-sonografia (US e a ressonância magnética (RM podem ser úteis na avaliação do comprometimento dos nervos periféricos auxiliando no diagnóstico das neurites, abscessos e no diagnóstico diferencial das síndromes compressivas.In leprosy, bone lesions due direct invasion of bacilli are low in incidence and these lesions exhibit radiologic findings of acute and chronic osteomyelitis similar to those of other granulomatous infectious agents. The more common bone lesions are those due to injurious effects of trauma and infection imposed upon denervated tissues. Radiographycally are seen various degrees of reabsorption of the extremities involving hands and feet with the loss of digits and disorganizing arthropathies in small joints. The radiologic appearance are similar to other conditions in which there is sensory impairment like scleroderma, syringomielia and diabetes mellitus. The ultrasonography and magnetic resonance imaging (MRI can be helpful in evaluation of the involvement of the peripheral nerves helping in the diagnosis of the neuritis, abscess and differential diagnosis in compressive syndromes.

  13. Doppler-musical instrument

    Energy Technology Data Exchange (ETDEWEB)

    Sato, T.J. [National Research Institute for Metals, Tsukuba, Ibaraki (Japan); Watanabe, N. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Shibata, K. [Institute for Materials Research, Tohoku Univ., Sendai, Miyagi (Japan)

    2001-03-01

    We propose a possible ultra-high energy resolution backscattering spectrometer optimized to spallation neutron source. A combination of multi monochromator crystal and Doppler drive provides considerable neutron flux, together with the reasonable energy range -30 < E < 30 {mu}eV, even when the ultra-high energy resolution of {delta}E{approx}0.03 {mu}eV is attained. (author)

  14. Laser doppler perfusion imaging

    International Nuclear Information System (INIS)

    Waardell, K.

    1992-01-01

    Recording of tissue perfusion is important in assessing the influence of peripheral vascular diseases on the microcirculation. This thesis reports on a laser doppler perfusion imager based on dynamic light scattering in tissue. When a low power He-Ne laser beam sequentally scans the tissue, moving blood cells generate doppler components in the back-scattered light. A fraction of this light is detected by a photodetector and converted into an electrical signal. In the processor, a signal proportional to the tissue perfusion at each measurement site is calculated and stored. When the scanning procedure is completed, a color-coded perfusion image is presented on a monitor. To convert important aspects of the perfusion image into more quantitative parameters, data analysis functions are implemented in the software. A theory describing the dependence of the distance between individual measurement points and detector on the system amplification factor is proposed and correction algorithms are presented. The performance of the laser doppler perfusion imager was evaluated using a flow simulator. A linear relationship between processor output signal and flow through the simulator was demonstrated for blood cell concentrations below 0.2%. The median sampling depth of the laser beam was simulated by a Monte Carlo technique and estimated to 235 μm. The perfusion imager has been used in the clinic to study perfusion changes in port wine stains treated with argon laser and to investigate the intensity and extension of the cutaneous axon reflex response after electrical nerve stimulation. The fact that perfusion can be visualized without touching the tissue implies elimination of sterilization problems, thus simplifying clinical investigations of perfusion in association with diagnosis and treatment of peripheral vascular diseases. 22 refs

  15. Principles of doppler tomography

    International Nuclear Information System (INIS)

    Juhlin, P.

    1992-08-01

    This paper shows how the radon transform can be used to determine vector fields. A scheme to determine the velocity field of a moving fluid by measurements with a continuous doppler signal is suggested. When the flow is confined to a bounded domain, as is the case in most applications, it can be uniquely decomposed into one gradiental and one rotational part. The former vanishes if the fluid is incompressible and source-free, and the latter can be completely reconstructed by the methods proposed in this paper if the domain is simply connected. Special attention is paid to laminar flow in a long cylindrical vessel with circular cross-section. Under such conditions the flow profile becomes parabolic, which makes the vessel recognizable as a typical 'N-shaped' pattern in an image describing the rotation of the velocity field. The vessel yields the same doppler tomographic pattern, no matter how it is sectioned. The ideas presented should be applicable also when studying the flow in blood vessels, even if the flow profile in these is not quite parabolic. The discrepancies only make the 'N-shape' somewhat distorted

  16. Comparisons between PW Doppler system and enhanced FM Doppler system

    DEFF Research Database (Denmark)

    Wilhjelm, Jens E.; Pedersen, P. C.

    1995-01-01

    This paper presents a new implementation of an echo-ranging FM Doppler system with improved performance, relative to the FM Doppler system reported previously. The use of long sweeps provides a significant reduction in peak to average power ratio compared to pulsed wave (PW) emission. A PW Doppler...... system exploits the direct relationship between arrival time of the received signal and range from the transducer. In the FM Doppler systems, a similar relationship exists in the spectral domain of the demodulated received signals, so that range is represented by frequency. Thus, a shift in location...... of moving scatterers between consecutive emissions corresponds to a frequency shift in the spectral signature. The improvement relative to the earlier version of the FM Doppler system is attained by utilizing cross-correlation of real spectra rather than of magnitude spectra for assessing flow velocity...

  17. Deconvoluting double Doppler spectra

    International Nuclear Information System (INIS)

    Ho, K.F.; Beling, C.D.; Fung, S.; Chan, K.L.; Tang, H.W.

    2001-01-01

    The successful deconvolution of data from double Doppler broadening of annihilation radiation (D-DBAR) spectroscopy is a promising area of endeavour aimed at producing momentum distributions of a quality comparable to those of the angular correlation technique. The deconvolution procedure we test in the present study is the constrained generalized least square method. Trials with computer simulated DDBAR spectra are generated and deconvoluted in order to find the best form of regularizer and the regularization parameter. For these trials the Neumann (reflective) boundary condition is used to give a single matrix operation in Fourier space. Experimental D-DBAR spectra are also subject to the same type of deconvolution after having carried out a background subtraction and using a symmetrize resolution function obtained from an 85 Sr source with wide coincidence windows. (orig.)

  18. Adaptive Spectral Doppler Estimation

    DEFF Research Database (Denmark)

    Gran, Fredrik; Jakobsson, Andreas; Jensen, Jørgen Arendt

    2009-01-01

    . The methods can also provide better quality of the estimated power spectral density (PSD) of the blood signal. Adaptive spectral estimation techniques are known to pro- vide good spectral resolution and contrast even when the ob- servation window is very short. The 2 adaptive techniques are tested......In this paper, 2 adaptive spectral estimation techniques are analyzed for spectral Doppler ultrasound. The purpose is to minimize the observation window needed to estimate the spectrogram to provide a better temporal resolution and gain more flexibility when designing the data acquisition sequence...... and compared with the averaged periodogram (Welch’s method). The blood power spectral capon (BPC) method is based on a standard minimum variance technique adapted to account for both averaging over slow-time and depth. The blood amplitude and phase estimation technique (BAPES) is based on finding a set...

  19. Emprego do ultra-som modo B e com efeito Doppler, termômetro infravermelho e medidas antropométricas na avaliação de uma formulação cosmética anticelulítica contendo extrato hidroglicólico de Trichilia catigua e Ptychopetalum olacoides Bentham

    OpenAIRE

    Idalina Maria Nunes Salgado Reis dos Santos

    2005-01-01

    Hidrolipodistrofia ginóide (H.L.D.G.), a celulite, é comumente tratada com cosméticos contendo extratos vegetais. O estudo realizado foi: ultra-sonografia na avaliação da espessura da hipoderme e a microcirculação cutânea; uso de termômetro infravermelho na medida da temperatura e análise das medidas antropométricas da uma formulação cosmética anticelulítica contendo extrato hidroglicólico de Trichilia catigua e Ptychopetalum olacoides Bentham (catuaba e marapuama). Foram realizadas medidas i...

  20. Transversal Doppler-Fizeau effect

    International Nuclear Information System (INIS)

    Subacius, E.

    1981-01-01

    The relativistic calculation of the Doppler-Fizeau effect foresees a second grade redshift due to the proper time dilation of a moving object. The relevance of this relativistic effect on astrophysical observation is discussed, herein. (Auhor) [pt

  1. Dual-Doppler Feasibility Study

    Science.gov (United States)

    Huddleston, Lisa L.

    2012-01-01

    When two or more Doppler weather radar systems are monitoring the same region, the Doppler velocities can be combined to form a three-dimensional (3-D) wind vector field thus providing for a more intuitive analysis of the wind field. A real-time display of the 3-D winds can assist forecasters in predicting the onset of convection and severe weather. The data can also be used to initialize local numerical weather prediction models. Two operational Doppler Radar systems are in the vicinity of Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS); these systems are operated by the 45th Space Wing (45 SW) and the National Weather Service Melbourne, Fla. (NWS MLB). Dual-Doppler applications were considered by the 45 SW in choosing the site for the new radar. Accordingly, the 45th Weather Squadron (45 WS), NWS MLB and the National Aeronautics and Space Administration tasked the Applied Meteorology Unit (AMU) to investigate the feasibility of establishing dual-Doppler capability using the two existing systems. This study investigated technical, hardware, and software requirements necessary to enable the establishment of a dual-Doppler capability. Review of the available literature pertaining to the dual-Doppler technique and consultation with experts revealed that the physical locations and resulting beam crossing angles of the 45 SW and NWS MLB radars make them ideally suited for a dual-Doppler capability. The dual-Doppler equations were derived to facilitate complete understanding of dual-Doppler synthesis; to determine the technical information requirements; and to determine the components of wind velocity from the equation of continuity and radial velocity data collected by the two Doppler radars. Analysis confirmed the suitability of the existing systems to provide the desired capability. In addition, it is possible that both 45 SW radar data and Terminal Doppler Weather Radar data from Orlando International Airport could be used to alleviate any

  2. Glare Spot Phase Doppler Anemometry

    OpenAIRE

    Hespel, Camille; Ren, Kuan Fang; Gréhan, Gérard; Onofri, Fabrice

    2006-01-01

    International audience; The Phase Doppler anemometry has been developed to measure simultaneously the velocity and the size of droplets. The measurement of the refractive index is also necessary since it depends on the temperature and the composition of the particle and its measurement permits both to increase the quality of the diameter measurement and to obtain information on the temperature and/or the composition of the droplets. In this paper, we introduce a Glare Spot Phase Doppler Anemo...

  3. Doppler echocardiography in pediatric cardiology

    International Nuclear Information System (INIS)

    Allen, H.D.; Marx, G.R.

    1986-01-01

    Congenital heart disease encompasses abnormalities in cardiac development which generally have in common either valve stenoses or connections between chambers or great vessels. Usually, abnormalities of intracardiac anatomy, and often, abnormalities of great vessel anatomy, can be unraveled by two-dimensional echocardiography. However, echocardiography offers little information regarding flow characteristics in the various congenital lesions. Addition of the Doppler principle, particularly when combined with the two-dimensional examination, can characterize the source of a flow disturbance, quantify gradients across a site of obstruction, and quantify flow volume across sites where flow is nonturbulent. These features make Doppler echocardiography unique for noninvasive accurate evaluation of children and adults with various forms of congenital heart disease. In this report, the authors discuss some of the present uses of Doppler echocardiography in congenital heart disease. Application of this technique requires greater understanding of certain physics principles than does routine echocardiography

  4. Doppler broadening of cross sections

    International Nuclear Information System (INIS)

    Buckler, P.A.C.; Pull, I.C.

    1962-12-01

    Expressions for temperature dependent cross-sections in terms of resonance parameters are obtained, involving generalisations of the conventional Doppler functions, ψ and φ. Descriptions of Fortran sub-routines, which calculate broadened cross-sections in accordance with the derived formulae, are included. (author)

  5. Tratamento de linfocele inguinal pós-operatória com injeção de cola de fibrina: relato de caso Treatment of postoperative inguinal lymphocele with fibrin glue injection: case report

    Directory of Open Access Journals (Sweden)

    Priscila Nunes Boaventura

    2007-06-01

    Full Text Available O paciente desenvolveu linforragia na região inguinal direita, depois de ponte aorto-bifemoral com enxerto de dácron®. Não respondeu ao tratamento conservador com cuidados locais e compressão. Foi realizado exame de ultra-sonografia Doppler, que evidenciou grande linfocele (6,4 x 3,36 x 6,1 cm, tratada pelo esvaziamento da loja por aspiração e injeção de cola de fibrina (1,6 mL em seu interior. O paciente se recuperou sem intercorrências e sem recidiva, após 3 meses de seguimento.The patient developed lymphatic drainage in the right groin after an aortobifemoral bypass with Dacron® graft. Conservative treatment with local wound care and compression was unsuccessful. Duplex scan showed a 6.4 x 3.36 x 6.1 cm lymphocele, which was treated by aspiration and injection of fibrin glue (1.6 mL. The patient recovered uneventfully and without recurrence after a 3-month follow-up.

  6. Anomalous Doppler effects in bulk phononic crystal

    International Nuclear Information System (INIS)

    Cai Feiyan; He Zhaojian; Zhang Anqi; Ding Yiqun; Liu Zhengyou

    2010-01-01

    Doppler effects in simple cubic phononic crystal are studied theoretically and numerically. In addition to observing Doppler shifts from a moving source's frequencies inside the gap, we find that Doppler shifts can be multi-order, anisotropic, and the dominant order of shift depends on the band index that the source's frequency is in.

  7. Spatial weighting of Doppler reactivity feedback

    International Nuclear Information System (INIS)

    Carew, J.F.; Diamond, D.J.; Todosow, M.

    1977-12-01

    The spatial weighting of the local Doppler feedback implicit in the determination of the core Doppler feedback reactivity has been investigated. Using a detailed planar PDQ7-II PWR model with local fuel-temperature feedback, the core Doppler spatial weight factor, S, has been determined for various control patterns and power levels. Assuming power-squared weighting of the local Doppler feedback, a simple analytic expression for S has been derived and, based on comparison with the PDQ7-II results, provides a convenient and accurate representation of the Doppler spatial weight factor. The sensitivity of these results to variations in the fuel rod heat transfer coefficients, fuel loading and the magnitude of the Doppler coefficient has also been evaluated. The dependence of the local Doppler coefficient on moderator temperature, boron concentration and control rod density has been determined and found to be weak. Selected comparisons with vendor analyses have been made and indicate general agreement

  8. A model for post-occlusive reactive hyperemia as measured with laser-Doppler perfusion monitoring

    NARCIS (Netherlands)

    de Mul, FFM; Morales, F; Smit, AJ; Graaff, R

    To facilitate the quantitative analysis of post-occlusive reactive fiyper emia (POR11), measured with laser-Doppler perfusion monitoring (LDPM) on extremities, we present a flow model for the dynamics of the perfusion of the tissue during PORH, based on three parameters: two time constants (tau(1)

  9. Doppler tomography in fusion plasmas and astrophysics

    DEFF Research Database (Denmark)

    Salewski, Mirko; Geiger, B.; Heidbrink, W. W.

    2015-01-01

    Doppler tomography is a well-known method in astrophysics to image the accretion flow, often in the shape of thin discs, in compact binary stars. As accretion discs rotate, all emitted line radiation is Doppler-shifted. In fast-ion Dα (FIDA) spectroscopy measurements in magnetically confined plasma......, the Dα-photons are likewise Doppler-shifted ultimately due to gyration of the fast ions. In either case, spectra of Doppler-shifted line emission are sensitive to the velocity distribution of the emitters. Astrophysical Doppler tomography has lead to images of accretion discs of binaries revealing bright...... and limits, analogies and differences in astrophysical and fusion plasma Doppler tomography and what can be learned by comparison of these applications....

  10. Measurement of ventricular function using Doppler ultrasound

    International Nuclear Information System (INIS)

    Teague, S.M.

    1986-01-01

    Doppler has wide application in the evaluation of valvular heart disease. The need to know ventricular function is a much more common reason for an echocardiographic evaluation. Interestingly, Doppler examinations can assess ventricular function from many perspectives. Description of ventricular function entails measurement of the timing, rate and volume of ventricular filling and ejection. Doppler ultrasound examination reveals all of these aspects of ventricular function noninvasively, simply, and without great expense or radiation exposure, as described in this chapter

  11. Direct Doppler auscultation of the carotid arteries

    International Nuclear Information System (INIS)

    Nix, L.

    1984-01-01

    The results of the carotid Doppler examinations and contrast arteriograms are presented. The overall sensitivity of the carotid Doppler examinations in detecting severe stenosis or occlusion of the carotid artery was 92%. The Doppler studies correctly differentiated these two conditions in 84% of the diseased vessels. In carotid arteries with stenosis greater than or equal to 50%, the sensitivity of the Doppler examinations was 90%, and these studies suggested stenosis in all but two of the 36 abnormal examinations. In two patent carotids with greater than 90% stenosis, a signal could not be elicited, presumably because of the low blood flow through the severely stenotic segment

  12. Avaliação do ombro em pacientes portadores de espondilite anquilosante por meio de ultra-som Evaluation of the shoulder in patients with ankylosing spondylitis with ultrasound

    Directory of Open Access Journals (Sweden)

    Ciro Yoshida Junior

    2008-04-01

    Full Text Available OBJETIVO: Descrever as principais alterações nos ombros de pacientes portadores de espondilite anquilosante (EA por meio de ultra-som (US e correlacionar os achados de imagem com a idade e o tempo de doença. MÉTODOS: Foram selecionados 35 pacientes com diagnóstico clínico de EA. Os pacientes foram submetidos a exame de ultra-sonografia dos ombros, sendo avaliados os tendões do manguito rotador quanto à sua ecotextura e espessura, o tendão do bíceps, a articulação acromioclavicular, os tubérculos umerais, a bursa subacromial-subdeltóidea, e a face posterior da articulação glenoumeral. Foram colhidos dados de tempo de doença, presença de dor nos ombros e freqüência das alterações das estruturas avaliadas. Os dados foram comparados com a idade e o tempo de doença, utilizando-se teste qui-quadrado e teste t de Student. RESULTADOS: Foi observada prevalência de 20% de alterações no manguito rotador, sendo 10% de tendinose/calcificação tendínea e 10% de rupturas tendíneas. A espessura média dos tendões do manguito rotador foi de 5,8 mm. As alterações ósseas nos tubérculos do úmero ocorreram em 84,3% dos ombros e as alterações acromioclaviculares em 54,3% dos ombros. CONCLUSÃO: Não há modificação da espessura dos tendões do manguito rotador relacionadas com o tempo de doença. Os principais achados de US, que se correlacionam com o tempo de doença na EA, são alterações ósseas nos tubérculos umerais e na articulação acromioclavicular. Não houve relação entre tempo de doença e presença de lesão tendínea.PURPOSE: To describe shoulder involvement and its prevalence with ultrasound in patients with ankylosing spondylitis and correlate the findings with age and duration of disease. METHODS: Ultrasound scans of both shoulders were performed in thirty five selected patients with clinical diagnosis of ankylosing spondylitis. Rotator cuff texture and thickness were evaluated as well as the biceps tendon

  13. Glare Spot Phase Doppler Anemometry

    Science.gov (United States)

    Hespel, Camille; Ren, Kuanfang; Gréhan, Gérard; Onofri, Fabrice

    2007-06-01

    The Phase Doppler anemometry has been developed to measure simultaneously the velocity and the size of droplets. The measurement of the refractive index would be also interesting since it depends on the temperature and the composition of the particle and its measurement permits both to increase the quality of the diameter measurement and to obtain information on the temperature and/or the composition of the droplets. In this paper, we introduce a Glare Spot Phase Doppler Anemometry which uses two large beams. In this case, the images of the particle formed by the reflected and refracted light, known as glare spots, are separated in space. When a particle passes in the probe volume, the two parts in a signal obtained by a detector in forward direction are then separated in time. If two detectors are used the phase differences between two signals, the distance and the intensity ratio of reflected and refracted parts can be obtained and they provide rich information about the particle diameter and its refractive index, as well as its velocity. This paper is devoted to the numerical study of such a configuration with two theoretical models: geometrical optics and rigorous electromagnetism solution.

  14. Radar Doppler Processing with Nonuniform Sampling.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Conventional signal processing to estimate radar Doppler frequency often assumes uniform pulse/sample spacing. This is for the convenience of t he processing. More recent performance enhancements in processor capability allow optimally processing nonuniform pulse/sample spacing, thereby overcoming some of the baggage that attends uniform sampling, such as Doppler ambiguity and SNR losses due to sidelobe control measures.

  15. Estimating the Doppler centroid of SAR data

    DEFF Research Database (Denmark)

    Madsen, Søren Nørvang

    1989-01-01

    attractive properties. An evaluation based on an existing SEASAT processor is reported. The time-domain algorithms are shown to be extremely efficient with respect to requirements on calculations and memory, and hence they are well suited to real-time systems where the Doppler estimation is based on raw SAR......After reviewing frequency-domain techniques for estimating the Doppler centroid of synthetic-aperture radar (SAR) data, the author describes a time-domain method and highlights its advantages. In particular, a nonlinear time-domain algorithm called the sign-Doppler estimator (SDE) is shown to have...... data. For offline processors where the Doppler estimation is performed on processed data, which removes the problem of partial coverage of bright targets, the ΔE estimator and the CDE (correlation Doppler estimator) algorithm give similar performance. However, for nonhomogeneous scenes it is found...

  16. Color doppler sonography in thickened gallbladder wall

    International Nuclear Information System (INIS)

    Han, Sang Suk; Choi, Seok Jin; Seo, Chang Hae; Eun, Choong Ki

    1996-01-01

    The thickening of the gallbladder wall is a valuable finding for the diagnosis of cholecystitis, but may be seen in non-cholecystic disease as well as in acute or chronic cholecystitis. The purpose of this study is to determine the value of color Doppler sonography in differentiating the causes of thickened gallbladder wall. Ninety eight patients with thickened gallbladder wall(more than 3mm) which was not due to gallbladder cancer were prospectively evaluated with color Doppler sonography. Sixty-six cases, confirmed by pathologic reports and clinical records, were analyzed for correlation between thickened gallbladder wall and color flow signal according to the underlying causes. Of the 66 patients, 28 cases were cholecystitis and 38 cases had non-cholecystic causes such as liver cirrhosis, ascites, hepatitis, pancreatitis, renal failure, and hypoalbuminemia. Of the 28 patients with cholecystitis(12 acute, 16 chronic), 23(82%) had color Doppler flow signals in the thickened gallbladder wall. Of the 38 patients with non-cholecystic causes, eight(21%) had color Doppler flow signals. There was a statistically significant difference of color Doppler flow signals between the cholecystitis and non-cholecystic groups(p=0.0001). No significant difference of color Doppler flow signals was found between cases of acute and chronic cholecystitis. Of the 23 patients with color Doppler flow signals in 28 cases of cholecystitis, 18(78.3%) showed a linear pattern and five(21.7%) showed a spotty pattern. Of the eight patients with color Doppler flow signals in the 38 non-cholecystic cases, four(50%) showed a linear pattern and four(50%) showed a spotty pattern. In cholecystitis, a linear color Doppler flow signal pattern is a much more frequent finding than a spotty pattern. Color Doppler sonography is a useful and adequate method for determining whether a thickened gallbladder wall is the result of cholecystitis or has non-cholecystic causes

  17. Color doppler imaging of subclavian steal phenomenon

    International Nuclear Information System (INIS)

    Cho, Nari Ya; Chung, Tae Sub; Kim, Jai Keun

    1997-01-01

    To evaluate the characteristic color doppler imaging of vertebral artery flow in the subclavian steal phenomenon. The study group consisted of eight patients with reversed vertebral artery flow proved by color Doppler imaging. We classified this flow into two groups:(1) complete reversal;(2) partial reversal, as shown by Doppler velocity waveform. Vertebral angiography was performed in six of eight patients;color Doppler imaging and angiographic findings were compared. On color Doppler imaging, all eight cases with reversed vertebral artery flow showed no signal at the proximal subclavian or brachiocephalic artery. We confirmed shunting of six cases by performing angiography from the contralateral vertebral and basilar artery to the ipsilateral vertebral artery. On the Doppler spectrum, six cases showed complete reversal and two partial reversal. On angiography, one partial reversal case showed complete occlusion of the subclavian artery with abundant collateral circulation of muscular branches of the vertebral artery. On color Doppler imaging, a reversed vertebral artery suggests the subclavian steal phenomenon. In particular, partial reversal waveform may reflect collateral circulation

  18. Patient-exposure data for doppler ultrasound

    International Nuclear Information System (INIS)

    Stewart, H.F.; Silvis, P.X.; Smith, S.W.

    1986-01-01

    In recent years ultrasound imaging and Doppler blood flow measurements have become important tools for use in diagnostic medicine. Commercial pulse-echo imaging equipment was first introduced into commerce in 1963. The first commercial continuous wave Doppler unit was introduced to the marketplace in 1966. As equipment improved and applications developed, the industry experienced rapid growth in the 1970s. One of the more recent growth areas in the application of diagnostic ultrasound has been the use of pulsed Doppler equipment for cardiac applications. Prior to 1976, some continuous wave Doppler ultrasound was used for cardiovascular diagnosis. However, only a single manufacturer marketed a pulsed Doppler clinical instrument for cardiac or peripheral vascular diagnosis. Currently, many continuous wave and pulsed Doppler instruments are commercially available for both peripheral vascular and cardiac diagnosis. This chapter (1) briefly reviews current safety guidelines, regulations, and recommendations for diagnostic ultrasound; (2) discusses the patient-exposure intensities associated with Doppler ultrasound medical equipment and compare these levels of exposure with intensities from other medical ultrasound devices; and (3) considers some of the current information as it relates to the safety of diagnostic ultrasound

  19. Doppler Velocity Signatures of Idealized Elliptical Vortices

    Directory of Open Access Journals (Sweden)

    Wen-Chau Lee

    2006-01-01

    Full Text Available Doppler radar observations have revealed a class of atmospheric vortices (tropical cyclones, tornadoes, dust devils that possess elliptical radar reflectivity signatures. One famous example is Typhoon Herb (1996 that maintained its elliptical reflectivity structure over a 40-hour period. Theoretical work and dual-Doppler analyses of observed tropical cyclones have suggested two physical mechanisms that can explain the formation of two types of elliptical vortices observed in nature, namely, the combination of a circular vortex with either a wavenumber two vortex Rossby wave or a deformation field. The characteristics of these two types of elliptical vortices and their corresponding Doppler velocity signatures have not been previously examined.

  20. Preliminary simulation study of doppler reflectometry

    International Nuclear Information System (INIS)

    Ishii, Yuta; Hojo, Hitoshi; Yoshikawa, Masashi; Ichimura, Makoto; Haraguchi, Yusuke; Imai, Tsuyoshi; Mase, Atsushi

    2010-01-01

    A preliminary simulation study of Doppler reflectometry is performed. The simulations solve Maxwell's equations by a finite difference time domain (FDTD) code method in two dimensions. A moving corrugated metal target is used as a plasma cutoff layer to study the basic features of Doppler reflectometry. We examined the effects of the full width at half maximum (FWHM) of the electromagnetic waves and the corrugation depth of the metal target. Furthermore, the effect of a nonuniform plasma is studied using this FDTD analysis. The Doppler shift and velocity are compared with those obtained from FDTD analysis of a uniform plasma. (author)

  1. Noncoherent Doppler tracking: first flight results

    Science.gov (United States)

    DeBoy, Christopher C.; Robert Jensen, J.; Asher, Mark S.

    2005-01-01

    Noncoherent Doppler tracking has been devised as a means to achieve highly accurate, two-way Doppler measurements with a simple, transceiver-based communications system. This technique has been flown as an experiment on the Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics (TIMED) spacecraft, (launched 7 December 2001), as the operational technique for Doppler tracking on CONTOUR, and is baselined on several future deep space missions at JHU/APL. This paper reports on initial results from a series of successful tests of this technique between the TIMED spacecraft and NASA ground stations in the Deep Space Network. It also examines the advantages that noncoherent Doppler tracking and a transceiver-based system may offer to small satellite systems, including reduced cost, mass, and power.

  2. Doppler coefficient measurements in Zebra Core 5

    International Nuclear Information System (INIS)

    Baker, A.R.; Wheeler, R.C.

    1965-11-01

    Measurements using a central hot loop in Zebra Core 5 are described. Results are given for the Doppler coefficients found in a number of assemblies with PuO 2 and 16% PuO 2 /84% depleted UO 2 pins, loaded with different combinations of steel, sodium or void pins. The mixed oxide results are in general about 20% more negative than was calculated using the FD2 data set, but agreement is good if the plutonium contributions in the calculations are omitted. The small positive Doppler coefficient calculated for Pu239 was not observed, and two measurements indicated instead a small negative effect. The Doppler effect in the mixed oxide systems was found to vary approximately as 1/T. The results from the empty loop and non-fissile assemblies indicate either a small negative Doppler effect in steel or alternatively the presence of an unexplained expansion effect. (author)

  3. Applications of Doppler in the first trimester

    International Nuclear Information System (INIS)

    Taylor, K.J.W.; Ramirez, B.; Grannum, P.

    1986-01-01

    Fifty patients have been studied by duplex Doppler US imaging in the first trimester. In normal gestations, luteal flow, characterized by a low pulsatility index (PI), can be seen in at least one ovary. Failure to detect luteal flow indicates a nonviable pregnancy. Six ectopic pregnancies demonstrated luteal flow and extrauterine heartbeat, detected by Doppler US. High PI values in the uterine artery are seen in the first trimester. Low PI values in the uterine arteries were found in patients with trophoblastic disease

  4. De-Dopplerization of Acoustic Measurements

    Science.gov (United States)

    2017-08-10

    accurate measurement of aircraft location to resample the time signal to account for the compression and expansion of acoustic wavefronts. Correcting...AFRL-RH-WP-TR-2017-0043 DE-DOPPLERIZATION OF ACOUSTIC MEASUREMENTS Frank Mobley, PhD 711 HPW/RHCB Wright-Patterson AFB OH...TITLE AND SUBTITLE DE-DOPPLERIZATION OF ACOUSTIC MEASUREMENTS 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER

  5. Aneurisma da artéria carótida interna extracraniana: relato de caso Aneurysm of the extracranial internal carotid artery: a case report

    Directory of Open Access Journals (Sweden)

    Marcio Ricardo Taveira Garcia

    2004-08-01

    Full Text Available Os aneurismas verdadeiros da artéria carótida interna extracraniana são raros, ao contrário dos supraclinóideos, somando menos de 4% dos aneurismas periféricos. Eles se apresentam clinicamente como massas palpáveis cervicais, junto à margem inferior do ângulo da mandíbula, causando rouquidão, disfagia e dor por compressão nervosa. Há freqüente associação desta doença com outros aneurismas periféricos devido à sua etiologia principal (aterosclerose. Os aneurismas periféricos são comumente identificados à ultra-sonografia Doppler, quando na vigência de janela acústica adequada. Nesta situação, os aneurismas podem ser avaliados tanto morfológica como hemodinamicamente. Sua identificação e estudo são importantes para prevenir graves complicações, como tromboses, infartos maciços ou embólicos da área correspondente no sistema nervoso central, ruptura e dissecção, além de auxiliar na indicação da melhor conduta terapêutica.Unlike supraclinoid aneurysms, true aneurysms of the extracranial internal carotid artery are extremely rare (less than 4% of the peripheral aneurysms. The commonest presentation is a pulsatile neck swelling below the angle of the jaw associated with hoarseness, dysphagia and pain (neural compression. Concomitance with other peripherical aneurysms is frequent and caused by atherosclerosis. The morphological and hemodynamic features are very well evaluated by Doppler ultrasound, when the acoustic window is satisfactory. Identification and evaluation of these aneurysms are very important to prevent thrombosis, rupture, dissections, massive strokes and embolic brain infarcts, besides helping in the decision of the best treatment.

  6. Refração atmosferica nas medidas Doppler

    OpenAIRE

    Oliveira, Leonardo Castro de

    1990-01-01

    Orientador: Jose Bittencourt de Andrade Dissertação (mestrado) - Universidade Federal do Parana. Setor de Tecnologia Resumo: Esta dissertação tem por objetivo realizar investigações referentes à refração atmosférica nas medidas Doppler. São considerados quatro modelos para correção troposférica, e o modelo de duas frequências para a correção da refração ionosférica . São também testados de diferentes fontes de dados meteorológicos. Todos os testes são feitos utilizando-se o programa GEO...

  7. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    Science.gov (United States)

    Goel, Sumit; Nagendrareddy, Suma Gundareddy; Raju, Manthena Srinivasa; Krishnojirao, Dayashankara Rao Jingade; Rastogi, Rajul; Mohan, Ravi Prakash Sasankoti; Gupta, Swati

    2011-01-01

    Aim: To evaluate the efficacy of ultrasonography (USG) with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Materials and Methods: Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. Results: USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas) of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas). There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. Conclusions: USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions. PMID:22223940

  8. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    International Nuclear Information System (INIS)

    Goel, Sumit; Nagendrareddy, Suma Gundareddy; Raju, Manthena Srinivasa; Krishnojirao, Dayashankara Rao Jingade; Rastogi, Rajul; Mohan, Ravi Prakash Sasankoti; Gupta, Swati

    2011-01-01

    To evaluate the efficacy of ultrasonography (USG) with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas) of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas). There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions

  9. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    Directory of Open Access Journals (Sweden)

    Sumit Goel

    2011-01-01

    Full Text Available Aim: To evaluate the efficacy of ultrasonography (USG with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Materials and Methods: Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. Results: USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas. There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. Conclusions: USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions.

  10. Análisis de perforantes de la epigástrica inferior profunda con Angio TC 3D, Eco Doppler color y Doppler simple de ultrasonidos en colgajo DIEP: resultados preliminares Analysis of deep inferior epigastric perforating vessels with 3D CT angiography, color Doppler ultrasonography and Doppler in diep flaps: preliminary results

    Directory of Open Access Journals (Sweden)

    J. Castro García

    2008-09-01

    Full Text Available Nuestro objetivo es la validación de la Angio TC tridimensional como herramienta de planificación de los colgajos DIEP, comparándolo con el Doppler de ultrasonidos (US y eco Doppler color. Entre enero de 2006 y marzo de 2007 se realiza en 11 pacientes (13 DIEP un estudio comparativo prospectivo entre el Doppler de US, eco Doppler color y Angio TC con reconstrucción tridimensional, utilizando como dato de referencia los hallazgos intraoperatorios. En dicho proceso se localiza la mejor perforante que pueda servir como pedículo al colgajo DIEP en función de su localización, calibre, trayecto y relaciones anatómicas con respecto al músculo. La Angio TC con reconstrucción tridimensional, demuestra una especificidad del 100% (IC 95% 75.3-100 lo que le convierte en una prueba con un alto valor predictivo positivo y una excelente herramienta en la planificación de los colgajos de perforantes. El eco Doppler color determinó, que tan sólo en un 46,1% (IC 95% 19,2-74,9 de los pacientes, la perforante seleccionada por la prueba de forma preoperatoria, coincidía con la perforante elegida en quirófano. Con el Doppler de US, en un 30,8 % (IC 95% 9,1-61,4 de los colgajos estudiados, coincidía la mejor perforante escogida de forma preoperatoria, con los hallazgos obtenidos tras la disección del colgajo. En el presente estudio, la Angio TC tridimensional se ha mostrado como una técnica con una gran especificidad que proporciona valiosa información, sólo comparable con la disección anatómica y por delante de pruebas como el Doppler de ultrasonidos y el eco Doppler color.The aim of this report, is to validate the Angio-CT technique with three-dimentional reconstruction as a preoperative planning tool, after comparison with Doppler ultrasound and color- Duplex. Between january 2006 and march 2007, we studied 11 consecutive patients (13 DIEP in whom a prospective comparative followed up was performed comparing, the findings observed using

  11. Doppler-guided retrograde catheterization system

    Science.gov (United States)

    Frazin, Leon J.; Vonesh, Michael J.; Chandran, Krishnan B.; Khasho, Fouad; Lanza, George M.; Talano, James V.; McPherson, David D.

    1991-05-01

    The purpose of this study was to investigate a Doppler guided catheterization system as an adjunctive or alternative methodology to overcome the disadvantages of left heart catheterization and angiography. These disadvantages include the biological effects of radiation and the toxic and volume effects of iodine contrast. Doppler retrograde guidance uses a 20 MHz circular pulsed Doppler crystal incorporated into the tip of a triple lumen multipurpose catheter and is advanced retrogradely using the directional flow information provided by the Doppler waveform. The velocity detection limits are either 1 m/second or 4 m/second depending upon the instrumentation. In a physiologic flow model of the human aortic arch, multiple data points revealed a positive wave form when flow was traveling toward the catheter tip indicating proper alignment for retrograde advancement. There was a negative wave form when flow was traveling away from the catheter tip if the catheter was in a branch or bent upon itself indicating improper catheter tip position for retrograde advancement. In a series of six dogs, the catheter was able to be accurately advanced from the femoral artery to the left ventricular chamber under Doppler signal guidance without the use of x-ray. The potential applications of a Doppler guided retrograde catheterization system include decreasing time requirements and allowing safer catheter guidance in patients with atherosclerotic vascular disease and suspected aortic dissection. The Doppler system may allow left ventricular pressure monitoring in the intensive care unit without the need for x-ray and it may allow left sided contrast echocardiography. With pulse velocity detection limits of 4 m/second, this system may allow catheter direction and passage into the aortic root and left ventricle in patients with aortic stenosis. A modification of the Doppler catheter may include transponder technology which would allow precise catheter tip localization once the

  12. MP3 compression of Doppler ultrasound signals.

    Science.gov (United States)

    Poepping, Tamie L; Gill, Jeremy; Fenster, Aaron; Holdsworth, David W

    2003-01-01

    The effect of lossy, MP3 compression on spectral parameters derived from Doppler ultrasound (US) signals was investigated. Compression was tested on signals acquired from two sources: 1. phase quadrature and 2. stereo audio directional output. A total of 11, 10-s acquisitions of Doppler US signal were collected from each source at three sites in a flow phantom. Doppler signals were digitized at 44.1 kHz and compressed using four grades of MP3 compression (in kilobits per second, kbps; compression ratios in brackets): 1400 kbps (uncompressed), 128 kbps (11:1), 64 kbps (22:1) and 32 kbps (44:1). Doppler spectra were characterized by peak velocity, mean velocity, spectral width, integrated power and ratio of spectral power between negative and positive velocities. The results suggest that MP3 compression on digital Doppler US signals is feasible at 128 kbps, with a resulting 11:1 compression ratio, without compromising clinically relevant information. Higher compression ratios led to significant differences for both signal sources when compared with the uncompressed signals. Copyright 2003 World Federation for Ultrasound in Medicine & Biology

  13. Editorial special issue on "Laser Doppler vibrometry"

    Science.gov (United States)

    Vanlanduit, Steve; Dirckx, Joris

    2017-12-01

    The invention of the laser in 1960 has opened up many opportunities in the field of measurement science and technology. Just a few years after the invention of the laser, a novel fluid flow measurement technique based on the Doppler effect was introduced: at that moment the laser Doppler anemometer or shortly LDA [1] was born. The technique enabled fluid velocity measurement by using the light of a He-Ne beam which was scattered by very small polystyrene spheres entrained in the fluid. Later on, in the late nineteen seventees it was recognized that the detection of the Doppler frequency shift that occurs when light is scattered by a moving surface can also be used to measure the vibration velocity of an object. The instrument to perform these vibration measurements was called the laser Doppler vibrometer or LDV [2]. In the last decades several technological advances were made in the field of laser Doppler vibrometry. The result is that nowadays, velocity measurements of fluids (using LDA) and vibrating objects (using LDV) are performed in many challenging applications in different fields (microelectronics, civil structures, biomedical engineering, material science, etc.).

  14. Development of the doppler electron velocimeter: theory.

    Energy Technology Data Exchange (ETDEWEB)

    Reu, Phillip L.

    2007-03-01

    Measurement of dynamic events at the nano-scale is currently impossible. This paper presents the theoretical underpinnings of a method for making these measurements using electron microscopes. Building on the work of Moellenstedt and Lichte who demonstrated Doppler shifting of an electron beam with a moving electron mirror, further work is proposed to perfect and utilize this concept in dynamic measurements. Specifically, using the concept of ''fringe-counting'' with the current principles of transmission electron holography, an extension of these methods to dynamic measurements is proposed. A presentation of the theory of Doppler electron wave shifting is given, starting from the development of the de Broglie wave, up through the equations describing interference effects and Doppler shifting in electron waves. A mathematical demonstration that Doppler shifting is identical to the conceptually easier to understand idea of counting moving fringes is given by analogy to optical interferometry. Finally, potential developmental experiments and uses of a Doppler electron microscope are discussed.

  15. Arm locking with Doppler estimation errors

    Energy Technology Data Exchange (ETDEWEB)

    Yu Yinan; Wand, Vinzenz; Mitryk, Shawn; Mueller, Guido, E-mail: yinan@phys.ufl.ed [Department of Physics, University of Florida, Gainesville, FL 32611 (United States)

    2010-05-01

    At the University of Florida we developed the University of Florida LISA Interferometer Simulator (UFLIS) in order to study LISA interferometry with hardware in the loop at a system level. One of the proposed laser frequency stabilization techniques in LISA is arm locking. Arm locking uses an adequately filtered linear combination of the LISA arm signals as a frequency reference. We will report about experiments in which we demonstrated arm locking using UFLIS. During these experiments we also discovered a problem associated with the Doppler shift of the return beam. The initial arm locking publications assumed that this Doppler shift can perfectly be subtracted inside the phasemeter or adds an insignificant offset to the sensor signal. However, the remaining Doppler knowledge error will cause a constant change in the laser frequency if unaccounted for. Several ways to circumvent this problem have been identified. We performed detailed simulations and started preliminary experiments to verify the performance of the proposed new controller designs.

  16. Inline Ultrasonic Rheometry by Pulsed Doppler

    Energy Technology Data Exchange (ETDEWEB)

    Pfund, David M.; Greenwood, Margaret S.; Bamberger, Judith A.; Pappas, Richard A.

    2006-12-22

    This will be a discussion of the non-invasive determination of the viscosity of a non-Newtonian fluid in laminar pipe flow over the range of shear rates present in the pipe. The procedure used requires knowledge of the flow profile in and the pressure drop along a long straight run of pipe. The profile is determined by using a pulsed ultrasonic Doppler velocimeter. This approach is ideal for making non-invasive, real-time measurements for monitoring and control. Rheograms of a shear thinning, thixotropic gel will be presented. The operating parameters and limitations of the Doppler-based instrument will be discussed. The most significant limitation is velocity gradient broadening of the Doppler spectra near the walls of the pipe. This limitation can be significant for strongly shear thinning fluids (depending also on the ratio of beam to pipe diameter and the transducer's insertion angle).

  17. Molecules cooled below the Doppler limit

    Science.gov (United States)

    Truppe, S.; Williams, H. J.; Hambach, M.; Caldwell, L.; Fitch, N. J.; Hinds, E. A.; Sauer, B. E.; Tarbutt, M. R.

    2017-12-01

    Magneto-optical trapping and sub-Doppler cooling have been essential to most experiments with quantum degenerate gases, optical lattices, atomic fountains and many other applications. A broad set of new applications await ultracold molecules, and the extension of laser cooling to molecules has begun. A magneto-optical trap (MOT) has been demonstrated for a single molecular species, SrF, but the sub-Doppler temperatures required for many applications have not yet been reached. Here we demonstrate a MOT of a second species, CaF, and we show how to cool these molecules to 50 μK, well below the Doppler limit, using a three-dimensional optical molasses. These ultracold molecules could be loaded into optical tweezers to trap arbitrary arrays for quantum simulation, launched into a molecular fountain for testing fundamental physics, and used to study collisions and chemistry between atoms and molecules at ultracold temperatures.

  18. Wide Angle Michelson Doppler Imaging Interferometer (WAMDII)

    Science.gov (United States)

    Roberts, B.

    1986-01-01

    The wide angle Michelson Doppler imaging interferometer (WAMDII) is a specialized type of optical Michelson interferometer working at sufficiently long path difference to measure Doppler shifts and to infer Doppler line widths of naturally occurring upper atmospheric Gaussian line emissions. The instrument is intended to measure vertical profiles of atmospheric winds and temperatures within the altitude range of 85 km to 300 km. The WAMDII consists of a Michelson interferometer followed by a camera lens and an 85 x 106 charge coupled device photodiode array. Narrow band filters in a filter wheel are used to isolate individual line emissions and the lens forms an image of the emitting region on the charge coupled device array.

  19. Diabetic Nephropathy : Evaluation with Doppler Ultrasonography

    International Nuclear Information System (INIS)

    Sim, Jung Suk; Kim, Seung Hyup; Kang, Heung Sik; Park, Jae Hyung; Han, Man Chung

    1996-01-01

    To compare Doppler ultrasonography with laboratory tests in evaluation of diabetic nephropathy. Fifty-five patients (mean age = 60, M : F = 26 : 29) with diabetes mellitus underwent renal Doppler ultrasonography. Resistive indices were compared with degree of proteinuria, serum creatinine level, and creatinine clearance rate. Eighteen patients who showed no proteinuria or microscopic proteinuria had a mean resistive index (RI) of 0.72 (SD, 0.05), 16 patients with macroscopic proteinuria without nephrotic syndrome had a mean RI of 0.82 (SD, 0.13), and 21 patients with nephrotic syndrome had a mean RI of 0.90 (SD, 0.12). Renal RI correlated highly with serum creatinine level (r = 0.62) and creatinine clearance rate (r = -0.43). Renal Doppler ultrasonography provides a useful indication of renal function in diabetic nephropathy but cannot offer an advantage over conventional laboratory test

  20. Gallblader varices in children with portal cavernoma: duplex-Doppler and color Doppler ultrasound studies

    International Nuclear Information System (INIS)

    Muro, D.; Sanguesa, C.; Lopez, A.

    1998-01-01

    To determine the prevalence of varices in the gallbladder wall, observed by duplex-Doppler and color Doppler ultrasound, in children with cavernoma of the portal vein. Nineteen patients with portal hypertension were studied prospectively by duplex-Doppler and color Doppler ultrasound: 12 of the patients had developed a cavernoma of the portal vein. The presence of peri vesicular varices was assessed in the group of patients with portal cavernoma. Duplex-Doppler and color Doppler ultrasound disclosed the presence of varices in gallbladder wall in nine of the 12 patients (75%). The varices appeared as anechoic and serpiginous areas, and Doppler ultrasound revealed slowed venous flow. However, the three patients in whom gallbldder varices were not detected presented collateral gastric ciculation and spontaneous splenorenal shunt. Gallbladder varices are common in children with portal vein cavernoma; they present hepatopetal flow. Their developments is not related to the size of the portal cavernoma, the presence of spontaneous portosystemic shunts, or endoscopic obliteration of gastric and esophageal varices. The detection of gallbladder varices in patients with portal hypertension who are to undergo biliary surgery is highly important for the surgeon, helping to avoid perioperative complications. (Author) 15 refs

  1. Efeitos da Histerectomia Total Abdominal sobre o Fluxo Sangüíneo Ovariano Effect of Total Abdominal Hysterectomy on Ovarian Blood Supply

    Directory of Open Access Journals (Sweden)

    Eliana Aguiar Petri Nahás

    2002-06-01

    Full Text Available Objetivo: avaliar os efeitos da histerectomia total abdominal (HTA sobre o fluxo sangüíneo ovariano, em mulheres no menacme, por meio da dopplervelocimetria e ultra-sonografia transvaginal. Métodos: estudo prospectivo no qual foram incluídas 61 mulheres, com idade igual ou inferior a 40 anos. As pacientes foram divididas em dois grupos: G1, com 31 pacientes submetidas à HTA, e G2, com 30 mulheres normais não submetidas à cirurgia. Somente foram incluídas pacientes eumenorréicas, ovulatórias, não-obesas ou fumantes, sem cirurgias ou doenças ovarianas prévias. Avaliou-se o fluxo sangüíneo das artérias ovarianas, inicialmente e aos 6 e 12 meses, pelo índice de pulsatilidade (IP na dopplervelocimetria, e o volume ovariano pela ultra-sonografia transvaginal (US. Para análise estatística empregou-se teste t pareado, análise de perfil, teste de Friedman e teste de Mann-Whitney. Resultados: na comparação estatística inicial os grupos foram homogêneos quanto às características epidemiológicas e quanto aos demais parâmetros avaliados neste estudo. Nas pacientes submetidas à histerectomia, observaram-se aos 6 e 12 meses aumento do volume ovariano ao US e diminuição do IP avaliado pela dopplervelocimetria (pPurpose: to evaluate the effect of total abdominal hysterectomy on ovarian blood supply in women in reproductive age, using transvaginal color Doppler. Methods: a prospective study was carried out on 61 40-year-old or younger women. They were divided into two groups: G1, 31 patients submitted to hysterectomy, and G2, 30 normal women. Criteria of inclusion: normal ovarian function at baseline, normal body weight, without expasure to tobacco, no history of laparotomy or ovarian pathology. The pulsatility index (PI of ovarian arteries determined by Doppler and the transvaginal ultrasonographic measurement of the ovarian volume were performed at three moments: baseline, 6 and 12 months. Results: at baseline the groups were

  2. Proposed protocols for peripheral and renal Doppler

    International Nuclear Information System (INIS)

    Fonseca Portuguez, Adriana

    2009-01-01

    A literature review was performed in order to prepare a summary of the important concepts of Doppler and applications in peripheral vascular evaluation and renal. The normal characteristics are summarized and explained in each vascular system and diagnostic criteria of the disorders frequently encountered in practice. Requested more studies have been identified and proposed protocols and report sheets have been developed to standardize the methodology of realization of several Doppler studies. The variability between operators has been treated to reduce as much as possible and follow-up studies have provided in patients who need. (author) [es

  3. Peritendinous calcinosis of calcaneus tendon associated with dermatomyositis: correlation between conventional radiograph, ultrasound, magnetic resonance imaging and gross surgical pathology; Calcinose peritendinea do tendao calcaneo associada a dermatomiosite: correlacao entre radiografia convencional, ultra-sonografia, ressonancia magnetica e macroscopia cirurgica

    Energy Technology Data Exchange (ETDEWEB)

    Rosa, Ana Claudia Ferreira; Gomide, Lidyane Marques de Paula; Lemes, Marcella Stival [Universidade Federal de Goias (UFG), Goiana, GO (Brazil). Faculdade de Medicina. Hospital das Clinicas; Costa, Edegmar Nunes; Rocha, Valney Luiz da [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Faculdade de Medicina. Dept. de Ortopedia; Machado, Marcio Martins; Santos Junior, Rubens Carneiro dos; Barros, Nestor de; Cerri, Giovanni Guido [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Faculdade de Medicina. Dept. de Radiologia; Sernik, Renato Antonio [Sao Paulo Univ., SP (Brazil). Hospital das Clinicas. Inst. de Radiologia; Nunes, Rodrigo Alvarenga [Universidade do Vale do Sapucai (UNIVAS), Pouso Alegre, MG (Brazil). Faculdade de Ciencias Medicas; Albieri, Alexandre Daher [Hospital de Acidentados de Goiania, GO (Brazil)

    2006-01-15

    Interstitial calcinosis is an uncommon condition in which there is either localized or widely disseminated deposition of calcium in the skin, subcutaneous tissues, muscles, and tendons. Calcinosis is often associated with collagen diseases, scleroderma and dermatomyositis. The authors report a case of interstitial calcinosis associated with dermatomyositis studied with conventional radiograph, ultrasound and magnetic resonance imaging, and correlate the imaging findings with the results of surgical pathology gross examination. (author)

  4. Distribution of Doppler Redshifts of Associated Absorbers of SDSS ...

    Indian Academy of Sciences (India)

    The authors searched all ... quasar, where the contribution of the Doppler motion is relatively small. ..... might contribute to the Doppler redshift distribution. 5. ... out accounting for the contamination of intervening absorption systems, which can.

  5. GRIP DOPPLER AEROSOL WIND LIDAR (DAWN) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Doppler Aerosol WiNd Lidar (DAWN) Dataset was collected by the Doppler Aerosol WiNd (DAWN), a pulsed lidar, which operated aboard a NASA DC-8 aircraft...

  6. Operational Bright-Band Snow Level Detection Using Doppler Radar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A method to detect the bright-band snow level from radar reflectivity and Doppler vertical velocity data collection with an atmospheric profiling Doppler radar. The...

  7. TCSP ER-2 DOPPLER RADAR (EDOP) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The EDOP provides vertically profiled reflectivity and Doppler velocity at aircraft nadir along the flight track. The ER-2 Doppler radar (EDOP) is an X-band (9.6...

  8. ISAR imaging using the instantaneous range instantaneous Doppler method

    CSIR Research Space (South Africa)

    Wazna, TM

    2015-10-01

    Full Text Available In Inverse Synthetic Aperture Radar (ISAR) imaging, the Range Instantaneous Doppler (RID) method is used to compensate for the nonuniform rotational motion of the target that degrades the Doppler resolution of the ISAR image. The Instantaneous Range...

  9. Comparison of power Doppler and color Doppler ultrasonography in the detection of intrasticular blood flow of normal infants

    International Nuclear Information System (INIS)

    Shin, Sung Ran; Lee, Ho Kyoung; Lee, Won Gyun; Youk, Dong Joon; Rho, Taek Soo; Lee, Min Jin; Lee, Sang Chun

    1999-01-01

    To compare color Doppler ultrasonography (US) and power Doppler US in the detection of intratesticular blood flow in normal infants and to asses the symmetry of blood flow. Testicular blood flow was assessed prospectively in 100 testes of 50 infants with both power and color Doppler US. We compared the power Doppler with color Doppler to detect intratesticular blood. When the flow was detected, intratesticular blood flow was graded as follows: grade 1: single intratesticular Doppler signal ; grade 2: multiple intratesticular Doppler signals. The symmetry of intratesticular flow was assessed by using the same method. Intratesticular flow was detected in 72 (72%) and 68 (68%) testes on power and color Doppler US, respectively. In 76 testes (76%), intratesticular flow was detected in either one or both techniques. On power Doppler US, grade 1 was seen in 40 tests and grade 2 in 32 testes. On color Doppler US, grade 1 was noted in 52 testes and grade 2 in 16 testes. Testicular blood flow was symmetric on both power and color Doppler US in each patient. There was no difference between power Doppler and color Doppler ultrasonography in detecting intratesticular blood flow in normal infants.

  10. Transcranial Doppler velocimetry in aneurysmal subarachnoid haemorrhage

    DEFF Research Database (Denmark)

    Staalsø, J M; Edsen, T; Romner, B

    2013-01-01

    -coded transcranial Doppler (TCCD), with the secondary aim of describing prediction of angiographic vasospasm and mortality. METHODS: /st>Sixty patients and 70 healthy controls were each examined in duplicate by alternating operators. A total of 939 measurements divided on 201 examination sets were conducted by four...

  11. Doppler Sonographic Evaluation of Venogenic Extremity Swellings ...

    African Journals Online (AJOL)

    2017-09-14

    Sep 14, 2017 ... potentially lead to many complications including life-threatening pulmonary arterial thrombosis. Screening and confirmation ... and exclusion of acute lower extremity DVT. Duplex ultrasound is considered as the ... this study evaluates the role of Doppler sonography in the clinical management of suspected.

  12. Complex regression Doppler optical coherence tomography

    Science.gov (United States)

    Elahi, Sahar; Gu, Shi; Thrane, Lars; Rollins, Andrew M.; Jenkins, Michael W.

    2018-04-01

    We introduce a new method to measure Doppler shifts more accurately and extend the dynamic range of Doppler optical coherence tomography (OCT). The two-point estimate of the conventional Doppler method is replaced with a regression that is applied to high-density B-scans in polar coordinates. We built a high-speed OCT system using a 1.68-MHz Fourier domain mode locked laser to acquire high-density B-scans (16,000 A-lines) at high enough frame rates (˜100 fps) to accurately capture the dynamics of the beating embryonic heart. Flow phantom experiments confirm that the complex regression lowers the minimum detectable velocity from 12.25 mm / s to 374 μm / s, whereas the maximum velocity of 400 mm / s is measured without phase wrapping. Complex regression Doppler OCT also demonstrates higher accuracy and precision compared with the conventional method, particularly when signal-to-noise ratio is low. The extended dynamic range allows monitoring of blood flow over several stages of development in embryos without adjusting the imaging parameters. In addition, applying complex averaging recovers hidden features in structural images.

  13. Doppler Shift Compensation Schemes in VANETs

    Directory of Open Access Journals (Sweden)

    F. Nyongesa

    2015-01-01

    Full Text Available Over the last decade vehicle-to-vehicle (V2V communication has received a lot of attention as it is a crucial issue in intravehicle communication as well as in Intelligent Transportation System (ITS. In ITS the focus is placed on integration of communication between mobile and fixed infrastructure to execute road safety as well as nonsafety information dissemination. The safety application such as emergence alerts lays emphasis on low-latency packet delivery rate (PDR, whereas multimedia and infotainment call for high data rates at low bit error rate (BER. The nonsafety information includes multimedia streaming for traffic information and infotainment applications such as playing audio content, utilizing navigation for driving, and accessing Internet. A lot of vehicular ad hoc network (VANET research has focused on specific areas including channel multiplexing, antenna diversity, and Doppler shift compensation schemes in an attempt to optimize BER performance. Despite this effort few surveys have been conducted to highlight the state-of-the-art collection on Doppler shift compensation schemes. Driven by this cause we survey some of the recent research activities in Doppler shift compensation schemes and highlight challenges and solutions as a stock-taking exercise. Moreover, we present open issues to be further investigated in order to address the challenges of Doppler shift in VANETs.

  14. Fifty Years of HF Doppler Observations

    Directory of Open Access Journals (Sweden)

    T Ogawa

    2009-04-01

    Full Text Available High frequency Doppler observations of the ionosphere began in August of 1957 in Kyoto. The number of the observation points worldwide were about 40 in 1980 and are about 20 at present. By this method the movement of the ionosphere reflection height and electron density below the height can be observed. Such variations are occurred by a wide variety of sources.

  15. Ultrasonic Doppler color in glaucoma: Concordance study

    International Nuclear Information System (INIS)

    Uriza, Felipe; Useche, Nicolas

    2005-01-01

    Our study demonstrates that US color Doppler is a non invasive, reliable and reproducible method for the evaluation of the orbitary flow in normal and glaucomatous patients. However is suggested that every group evaluates the inter and intraobserver variability because of the lack of universal reference velocity measurements

  16. Aerosol distribution measurements by laser - Doppler - spectroscopy

    International Nuclear Information System (INIS)

    Baldassari, J.

    1977-01-01

    Laser-Doppler-Spectroscopy is used to study particle size distribution, especially sodium aerosols, in the presence of uncondensable gases. Theoretical basis are given, and an experimental technique is described. First theoretical results show reasonably good agreement with experimental data available; this method seems to be a promising one. (author)

  17. Laser Doppler thermometry in flat flames

    NARCIS (Netherlands)

    Maaren, van A.; Goey, de L.P.H.

    1994-01-01

    Laser Doppler Velocimetry measurements are performed in flat flames, stabilized on a newly developed flat-flame burner. It is shown that the velocity component perpendicular to the main flow direction, induced by expansion in the reaction zone and buoyancy in the burnt gas, is significant. A method

  18. TCSP ER-2 DOPPLER RADAR (EDOP) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The TCSP ER-2 DOPPLER RADAR (EDOP) dataset was collected by the ER-2 Doppler radar (EDOP), which is an X-band (9.6 GHz) Doppler radar mounted in the nose of the ER-2...

  19. CAMEX-4 ER-2 DOPPLER RADAR V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The CAMEX-4 ER-2 Doppler Radar dataset was collected by the ER-2 Doppler radar (EDOP), which is an X-band (9.6 GHz) Doppler radar mounted in the nose of ER-2. The...

  20. Radar micro-doppler signatures processing and applications

    CERN Document Server

    Chen, Victor C; Miceli, William J

    2014-01-01

    Radar Micro-Doppler Signatures: Processing and applications concentrates on the processing and application of radar micro-Doppler signatures in real world situations, providing readers with a good working knowledge on a variety of applications of radar micro-Doppler signatures.

  1. Doppler speedometer for micro-organisms

    International Nuclear Information System (INIS)

    Penkov, F.; Tuleushev, A.; Lisitsyn, V.; Kim, S.; Tuleushev, Yu.

    1996-01-01

    Objective of Investigations: Development and creation of the Doppler speedometer for micro-organisms which allows to evaluate, in a real temporal scale, variations in the state of water suspension of micro-organisms under the effect of chemical, physical and other external actions. Statement of the Problem The main problem is absence of reliable, accessible for users and simple, in view of application, Doppler speedometers for micro-organisms. Nevertheless, correlation Doppler spectrometry in the regime of heterodyning the supporting and cell-scattered laser radiation is welt known. The main idea is that the correlation function of photo-current pulses bears an information on the averages over the assembly of cell velocities. For solving the biological problems, construction of auto-correlation function in the real-time regime with the delay time values comprising, function in the real-time regime with the delay time values comprising, nearly, 100 me (10 khz) or higher is needed. Computers of high class manage this problem using but the program software. Due to this, one can simplify applications of the proposed techniques provided he creates the Doppler speedometer for micro-organism on a base of the P entium . Expected Result Manufactured operable mock-up of the Doppler speedometer for micro-organisms in a form of the auxiliary computer block which allows to receive an information, in the real time scale, on the results of external effects of various nature on the cell assembly in transparent medium with a small volume of the studied cell suspension

  2. The medical Doppler in hand surgery: its scientific basis, applications, and the history of its namesake, Christian Johann Doppler.

    Science.gov (United States)

    Ghori, Ahmer K; Chung, Kevin C

    2007-12-01

    The word Doppler is used synonymously in hand surgery for evaluating patency of vascular structures; however, the science and history behind the Doppler effect are not as well-known. We will present the theories behind the Doppler effect and the history of the person who made this discovery.

  3. Power and color Doppler ultrasound settings for inflammatory flow

    DEFF Research Database (Denmark)

    Torp-Pedersen, Søren; Christensen, Robin; Szkudlarek, Marcin

    2015-01-01

    OBJECTIVE: To determine how settings for power and color Doppler ultrasound sensitivity vary on different high- and intermediate-range ultrasound machines and to evaluate the impact of these changes on Doppler scoring of inflamed joints. METHODS: Six different types of ultrasound machines were used....... On each machine, the factory setting for superficial musculoskeletal scanning was used unchanged for both color and power Doppler modalities. The settings were then adjusted for increased Doppler sensitivity, and these settings were designated study settings. Eleven patients with rheumatoid arthritis (RA......) with wrist involvement were scanned on the 6 machines, each with 4 settings, generating 264 Doppler images for scoring and color quantification. Doppler sensitivity was measured with a quantitative assessment of Doppler activity: color fraction. Higher color fraction indicated higher sensitivity. RESULTS...

  4. Transcranial Doppler sonography in familial hemiplegic migraine

    International Nuclear Information System (INIS)

    Pierelli, F.; Pauri, F.; Cupini, L.M.; Fiermonte, G.; Rizzo, P.A.

    1991-01-01

    A patient affected by familial hemiplegic migraine underwent transcranial Doppler sonography twice: the first during a spontaneous attack with right hemiparesis and aphasia, the second during a headachefree period. During the attack the following haemodynamic changes were seen: (a) bilateral increase in the middle cerebral artery and anterior cerebral artery blood flow velocities (this increase was more pronounced on the left side), (b) decreased systo-diastolic ratio and pulsatility index on the right side, (c) increased systo-diastolic ratio and pulsatility index on the left side. The results indicate that during the attack in this familial hemiplegic migraine patient, a diffuse vasoconstriction of the basal cerebral arteries developed. Moreover, transcranial Doppler sonography data suggest that a prolonged vasoconstriction of the peripheral arterioles could play a role in determining the neurological symptoms in this syndrome. 13 refs., 1 figs., 1 tab

  5. Color Doppler US of the penis

    Energy Technology Data Exchange (ETDEWEB)

    Bertolotto, Michele (ed.) [Trieste Univ. Ospedale di Cattinara (Italy). Dept. Radiology

    2008-07-01

    This book provides a comprehensive reference and practical guide on the application of US to penile diseases and conditions. After introductory chapters on technical requirements and penile anatomy, subsequent chapters offer a systematic overview of the diverse applications of color Doppler US. The topics covered include erectile dysfunction, Peyronie's disease, priapism, trauma, tumors, the postoperative penis, inflammation, and fibrosis. Each topic is introduced by a clinical overview with the purpose of clarifying the problems and elucidating what the urologist may expect from color Doppler US. Thereafter, performance of the US study is explained and the pathological anatomy reviewed. High-quality images obtained with high-end US equipment are included. Each chapter also contains a section on the diagnostic information provided by other imaging modalities, and in particular MRI. (orig.)

  6. Transcranial Doppler sonography in familial hemiplegic migraine

    Energy Technology Data Exchange (ETDEWEB)

    Pierelli, F.; Pauri, F.; Cupini, L.M.; Fiermonte, G.; Rizzo, P.A. (Universita la Sapienza, Roma (Italy))

    1991-02-01

    A patient affected by familial hemiplegic migraine underwent transcranial Doppler sonography twice: the first during a spontaneous attack with right hemiparesis and aphasia, the second during a headachefree period. During the attack the following haemodynamic changes were seen: (a) bilateral increase in the middle cerebral artery and anterior cerebral artery blood flow velocities (this increase was more pronounced on the left side), (b) decreased systo-diastolic ratio and pulsatility index on the right side, (c) increased systo-diastolic ratio and pulsatility index on the left side. The results indicate that during the attack in this familial hemiplegic migraine patient, a diffuse vasoconstriction of the basal cerebral arteries developed. Moreover, transcranial Doppler sonography data suggest that a prolonged vasoconstriction of the peripheral arterioles could play a role in determining the neurological symptoms in this syndrome. 13 refs., 1 figs., 1 tab.

  7. Renal duplex Doppler ultrasound findings in diabetics

    International Nuclear Information System (INIS)

    Shim, Hyang Yee; Kim, Young Geun; Kook, Cheol Keu; Yoon, Chong Hyun; Lee, Shin Hyung; Lee, Chang Joon

    1993-01-01

    The correlation between clinical-laboratory findings and renal duplex Doppler ultrasound findings was studied in 45 patients with diabetes mellitus to see the role of duplex Doppler ultrasound in the detection of diabetic nephropathy. The resistive indices in patients with elevated serum creatinine, BUN, proteinuria, and systolic blood pressure levels were statistically significantly higher than those in patients with normal levels (p<0.05). Also resistive indics in patients with retinopathy were higher than that in patients without retinopathy (p<0.05). But the ultrasound morphologic changes of kidney such as renal length, cortical eye-catching, and corticomedullarycontrast were not well correlated with clinical-laboratory data and resistive index. The resistive index of the kidney in conjunction with clinical-laboratory data in diabetics may be helpful in the evaluation of diabetic nephropathy

  8. Renal duplex Doppler ultrasound findings in diabetics

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Hyang Yee; Kim, Young Geun; Kook, Cheol Keu; Yoon, Chong Hyun; Lee, Shin Hyung; Lee, Chang Joon [National Medical Center, Seoul (Korea, Republic of)

    1993-12-15

    The correlation between clinical-laboratory findings and renal duplex Doppler ultrasound findings was studied in 45 patients with diabetes mellitus to see the role of duplex Doppler ultrasound in the detection of diabetic nephropathy. The resistive indices in patients with elevated serum creatinine, BUN, proteinuria, and systolic blood pressure levels were statistically significantly higher than those in patients with normal levels (p<0.05). Also resistive indics in patients with retinopathy were higher than that in patients without retinopathy (p<0.05). But the ultrasound morphologic changes of kidney such as renal length, cortical eye-catching, and corticomedullarycontrast were not well correlated with clinical-laboratory data and resistive index. The resistive index of the kidney in conjunction with clinical-laboratory data in diabetics may be helpful in the evaluation of diabetic nephropathy

  9. Colour Doppler ultrasound of the penis

    Energy Technology Data Exchange (ETDEWEB)

    Wilkins, C.J.; Sriprasad, S.; Sidhu, P.S. E-mail: paulsidhu@compuserve.com

    2003-07-01

    Because it is a superficial structure, the penis is ideally suited to ultrasound imaging. A number of disease processes, including Peyronie's disease, penile fractures and penile tumours, are clearly visualized with ultrasound. An assessment of priapism can also be made using spectral Doppler waveform technology. Furthermore, dynamic assessment of cavernosal arterial changes after pharmaco-stimulation allows diagnosis of arterial and venogenic causes for impotence. This pictorial review illustrates the range of diseases encountered with ultrasound of the penis.

  10. Doppler Lidar Wind Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Newsom, R. K. [DOE ARM Climate Research Facility, Washington, DC (United States); Sivaraman, C. [DOE ARM Climate Research Facility, Washington, DC (United States); Shippert, T. R. [DOE ARM Climate Research Facility, Washington, DC (United States); Riihimaki, L. D. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-07-01

    Wind speed and direction, together with pressure, temperature, and relative humidity, are the most fundamental atmospheric state parameters. Accurate measurement of these parameters is crucial for numerical weather prediction. Vertically resolved wind measurements in the atmospheric boundary layer are particularly important for modeling pollutant and aerosol transport. Raw data from a scanning coherent Doppler lidar system can be processed to generate accurate height-resolved measurements of wind speed and direction in the atmospheric boundary layer.

  11. Recommendations for terminology and display for doppler echocardiography

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Doppler echocardiography has recently emerged as a major noninvasive technique with many applications in cardiology. To a large extent, this has been based upon a combination of clinical and engineering advances which now make possible the use of quantitative Doppler echocardiography in combination with two-dimensional imaging for measurement of volume flows, transvalve gradients, and other physiologic flow parameters which reflect cardiac function. It was the purpose of this Committee to provide a glossary of terms which could be used in standard fashion for papers and discussions related to Doppler echocardiography. As part of its task, the Committee also undertook an attempt to recommend a standard for display of Doppler information which would be useful, both for manufacturers and for clinicians. The document, therefore, includes: Section I, the Committee's recommendations for Doppler display. Section II, the glossary of Doppler terms, related to engineering and to clinical applications

  12. The image of urachus adenocarcinoma on Doppler ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Oyar, Orhan E-mail: o_oyar@hotmail.com; Yesildag, Ahmet; Gulsoy, Ufuk Kemal; Perk, Hakki

    2002-10-01

    Malignant urachal lesions are exceedingly rare and occur predominantly in adult life. In this case report, an adult patient with urachal carcinoma is presented with abdominal plain film, intravenous urography, gray-scale ultrasonography (US), Doppler US, and computed tomography (CT). Doppler US successfully showed the neovascularity with low resistive index value in the urachus tumor. We believe that Doppler US examination is helpful in the differential diagnosis of urachal carcinoma.

  13. Doppler US evaluation of the hypertensive portal system

    International Nuclear Information System (INIS)

    Needleman, L.; Kurtz, A.B.; Bezzi, M.; Rifkin, M.D.; Pasto, M.E.; Pennell, R.G.; Baltarowich, O.H.; Goldberg, B.B.

    1986-01-01

    In patients with known portal hypertension, pulsed Doppler US was used for qualitative and directional evaluation of flow in the portal venous system and collateral vessels. Most patients had normal hepatopetal flow. Doppler US revealed the following abnormal blood flow patterns: hepatofugal portal flow, bidirectional portal flow, intrahepatic portal shunting, flow in portasystemic collaterals, and hepatic vein obstruction. Doppler US can provide important clinical information in the evaluation of portal hypertension

  14. New Insights from Inside-Out Doppler Tomography

    Directory of Open Access Journals (Sweden)

    E. J. Kotze

    2015-02-01

    Full Text Available We present preliminary results from our investigation into using an “inside-out” velocity space for creating a Doppler tomogram. The aim is to transpose the inverted appearance of the Cartesian velocity space used in normal Doppler tomography. In a comparison between normal and inside-out Doppler tomograms of cataclysmic variables, we show that the inside-out velocity space has the potential to produce new insights into the accretion dynamics in these systems.

  15. Power doppler 'blanching' after the application of transducer pressure

    International Nuclear Information System (INIS)

    Joshua, F.; Edmonds, J.; Lassere, M.; De Carle, R.; Rayment, M.; Bryant, C.; Shnier, R.

    2005-01-01

    The aim of this study was to determine if transducer pressure modifies power Doppler assessments of rheumatoid arthritis synovium at the metacarpophalangeal joints and metatarsophalangeal joints. Five rheumatoid arthritis patients of varying degrees of 'disease activity' and damage were assessed with power Doppler ultrasound scanning of the dominant hand second to fifth metacarpophalangeal joints. Two rheumatoid arthritis patients had their dominant foot first to fifth metatarsophalangeal joints assessed with power Doppler ultrasound. Ultrasonography was performed with a high frequency transducer (14 MHz) with a colour mode frequency of 10 Mhz, and a standard colour box and gain. In the joint that showed the highest power Doppler signal, an image was made. A further image was taken after transducer pressure was applied. In all patients, there was increased flow to at least one joint. After pressure was applied, power Doppler signal intensity markedly reduced in all images and in some there was no recordable power Doppler signal. Increased transducer pressure can result in a marked reduction or obliteration in power Doppler signal. This power Doppler 'blanching' shows the need for further studies to evaluate sources of error and standardization before power Doppler ultrasound becomes a routine measure of 'disease activity' in rheumatoid arthritis. Copyright (2005) Blackwell Science Pty Ltd

  16. Evaluating Peripheral Vascular Injuries: Is Color Doppler Enough for Diagnosis?

    Directory of Open Access Journals (Sweden)

    Mohd Lateef Wani

    2014-03-01

    Full Text Available Background:: Vascular injury poses a serious threat to limb and life. Thus, diagnosis should be made immediately with minimally invasive methods. Doppler is a good aid in diagnosis of vascular injury. Methods:: The present prospective study was conducted on 150 patients who presented with soft signs (the signs which are suggestive but not confirmatory of vascular injury. They were subjected to color Doppler examination before exploration. The patients with the features of vascular injury on color Doppler were subjected to exploration. On the other hand, those who had normal Doppler were subjected to CT- angiography. Then, the findings of the exploration were matched with those of color Doppler. The data were analyzed using the SPSS statistical software. Results:: Out of the 150 Doppler examinations, 110 (73.33% were reported as positive, while 40 were reported as negative for vascular injury. These were subjected to CT-angiography and seven of them had the features of vascular injury on CT-angiography. All the patients with positive Doppler or CT angiography findings were subjected to exploration. Doppler had a sensitivity of 94% and specificity of 82.5% in diagnosis of vascular injury using Binary classification test. Conclusions:: Color Doppler is an easily available, reliable, and handy method of diagnosing a vascular injury. It has a very high sensitivity and specificity in diagnosis of vascular injuries.

  17. Coherent Detection in Laser Doppler Velocimeters

    DEFF Research Database (Denmark)

    Hanson, Steen Grüner

    1974-01-01

    , but intelligible particle picture of electromagnetic waves. The analysis is carried out with special emphasis on the heterodyning process in the laser Doppler velocimeter (LDV) because the main purpose of this article is to provide a better understanding of this instrument. An aid for this purpose......The possibility of heterodyning between electromagnetic waves scattered by particles separated in space is explained from a classical point of view and from a quantum mechanical point of view. The last description being carried out using only the Heisenberg uncertainty principle and a rather coarse...

  18. Digital setup for Doppler broadening spectroscopy

    International Nuclear Information System (INIS)

    Cizek, J; Vlcek, M; Prochazka, I

    2011-01-01

    New digital spectrometer for measurement of the Doppler shift of annihilation photons was developed and tested in this work. Digital spectrometer uses a fast 12-bit digitizer for direct sampling of signals from HPGe detectors. Analysis of sampled waveforms is performed off-line in software. Performance of the new digital setup was compared with its traditional analogue counterpart. Superior energy resolution was achieved in the digital setup. Moreover, the digital setup allows for a better control of the shape of detector signals. This enables to eliminate undesired signals damaged by pile-up effects or by ballistic deficit.

  19. Burst Format Design for Optimum Joint Estimation of Doppler-Shift and Doppler-Rate in Packet Satellite Communications

    Directory of Open Access Journals (Sweden)

    Luca Giugno

    2007-05-01

    Full Text Available This paper considers the problem of optimizing the burst format of packet transmission to perform enhanced-accuracy estimation of Doppler-shift and Doppler-rate of the carrier of the received signal, due to relative motion between the transmitter and the receiver. Two novel burst formats that minimize the Doppler-shift and the Doppler-rate Cramér-Rao bounds (CRBs for the joint estimation of carrier phase/Doppler-shift and of the Doppler-rate are derived, and a data-aided (DA estimation algorithm suitable for each optimal burst format is presented. Performance of the newly derived estimators is evaluated by analysis and by simulation, showing that such algorithms attain their relevant CRBs with very low complexity, so that they can be directly embedded into new-generation digital modems for satellite communications at low SNR.

  20. Celulitis por citomegalovirus

    Directory of Open Access Journals (Sweden)

    A. Ruiz Lascano

    2002-12-01

    Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.

  1. Doppler ultrasound scan during normal gestation: umbilical circulation; Ecografia Doppler en la gestacion normal: circulacion umbilical

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, T.; Sabate, J.; Martinez-Benavides, M. M.; Sanchez-Ramos, J. [Hospital Virgen Macarena. Sevilla (Spain)

    2002-07-01

    To determine normal umbilical circulation patterns by means of Doppler ultrasound scan in a healthy gestating population without risk factors and with normal perinatal results, and to evaluate any occurring modifications relative to gestational age by obtaining records kept during pregnancy. One hundred and sixteen pregnant women carrying a single fetus have been studied. These women had no risk factors, with both clinical and analytical controls, as well as ultrasound scans, all being normal. There were performed a total of 193 Doppler ultrasound scans between weeks 15 and 41 of gestation, with blood-flow analysis in the arteries and vein of the umbilical cord. The obtained information was correlated with parameters that evaluate fetal well-being (fetal monitoring and/or oxytocin test) and perinatal result (delivery type, birth weight, Apgar score). Statistical analysis was performed with the programs SPSS 6.0.1 for Windows and EPIINFO 6.0.4. With pulsed Doppler, the umbilical artery in all cases demonstrated a biphasic morphology with systolic and diastolic components and without retrograde blood flow. As the gestation period increased, there was observed a progressive decrease in resistance along with an increase in blood-flow velocity during the diastolic phase. The Doppler ultrasound scan is a non-invasive method that permits the hemodynamic study of umbilical blood circulation. A knowledge of normal blood-flow signal morphology, as well as of the normal values for Doppler indices in relation to gestational age would permit us to utilize this method in high-risk pregnancies. (Author) 30 refs.

  2. Quality Control of Wind Data from 50-MHz Doppler Radar Wind Profiler

    Science.gov (United States)

    Vacek, Austin

    2016-01-01

    Upper-level wind profiles obtained from a 50-MHz Doppler Radar Wind Profiler (DRWP) instrument at Kennedy Space Center are incorporated in space launch vehicle design and day-of-launch operations to assess wind effects on the vehicle during ascent. Automated and manual quality control (QC) techniques are implemented to remove spurious data in the upper-level wind profiles caused from atmospheric and non-atmospheric artifacts over the 2010-2012 period of record (POR). By adding the new quality controlled profiles with older profiles from 1997-2009, a robust database will be constructed of upper-level wind characteristics. Statistical analysis will determine the maximum, minimum, and 95th percentile of the wind components from the DRWP profiles over recent POR and compare against the older database. Additionally, this study identifies specific QC flags triggered during the QC process to understand how much data is retained and removed from the profiles.

  3. Ambiguity resolution for satellite Doppler positioning systems

    Science.gov (United States)

    Argentiero, P.; Marini, J.

    1979-01-01

    The implementation of satellite-based Doppler positioning systems frequently requires the recovery of transmitter position from a single pass of Doppler data. The least-squares approach to the problem yields conjugate solutions on either side of the satellite subtrack. It is important to develop a procedure for choosing the proper solution which is correct in a high percentage of cases. A test for ambiguity resolution which is the most powerful in the sense that it maximizes the probability of a correct decision is derived. When systematic error sources are properly included in the least-squares reduction process to yield an optimal solution the test reduces to choosing the solution which provides the smaller valuation of the least-squares loss function. When systematic error sources are ignored in the least-squares reduction, the most powerful test is a quadratic form comparison with the weighting matrix of the quadratic form obtained by computing the pseudoinverse of a reduced-rank square matrix. A formula for computing the power of the most powerful test is provided. Numerical examples are included in which the power of the test is computed for situations that are relevant to the design of a satellite-aided search and rescue system.

  4. Color Doppler Ultrasonographic Features of Hashimoto's Thyroiditis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo Hyuk; Kim, Mie Young; Rho, Eun Jin; Yi, Jeong Geun; Han, Chun Hwan [Kangnam General Hospital Public Corporation, Seoul (Korea, Republic of); Hwang, Hee Yong [Choong Ang Gil Hospital, Incheon (Korea, Republic of)

    1995-06-15

    Color Doppler ultrasonographic(US) features of 28 patients with Hashimato's thyroiditis were evaluated with regard to echo and color-flow patterns. Correlation of color-flow pattern with thyroid function was performed. All 28 patients showed varying degrees of diffuse enlargement of the thyroid gland and a heterogeneous echo pattern.Color-flow pattern of increased blood flow. Low to moderate, focally increased blood flow was seen in 26 patients(92.8%). Of these 26 patients, 24 patients showed subclinical hypothyroidism or euthyroidism. Two patients who showed hyperthyroidism showed several pieces of focally increased color flow, Which was noted during both systole and diastole. Diffuse, multifocal color-flow throughout thyroid gland was seen in two patients with Hashimato's thyroiditis: one with clinical hypothyroidism and the other with subclinical hypothyroidism. Even though Hashimoto's thyroiditis showed variable color-flow patterns, we believe that heterogenous parenchymal echopattern with low or moderately increased flow is a rather characteristic feature of Hashimoto's thyroiditis, and we suggest that color Doppler US provides additional information for evaluation of Hashimoto's thyroiditis

  5. Enormous periodic doppler shifts in SS 433

    International Nuclear Information System (INIS)

    Margon, B.; Ford, H.C.; Grandi, S.A.; Stone, R.P.S.

    1979-01-01

    We have previously reported prominent ''moving' emission lines in the visible spectrum of Stephenson-Sanduleak 433, the optical counterpart of a variable radio and X-ray source. Further observations show that despite the implausible velocities and changes in velocities implied if the moving features are interpreted as Doppler-shifted Balmer lines, this explanation is indeed correct. Spectroscopy of SS 433 on 51 mights in 1978--1979 reveals that the unidentified features are two sets of Balmer and He I lines, one with large and changing redshift, and the other with large and changing blueshift. Combining our data with published earlier observations, we obtain Doppler shifts on 80 nights in the period 1978 June to 1979 June. These data indicate that the velocity variations are cyclical, repeating in both the blueshift and redshift systems with a period of 164 +- 3 days. The two systems have thus far been observed to reach maximum positive and negative radial velocities of +50,000 and -35,000 km s -1 , respectively, are always symmetric about redshift z=0.04, and follow roughly sinusoidal velocity curves. We discuss in addition a variety of interesting short-term spectroscopic details, including minor but highly significant deviations of the radial velocity from the sinusoid, and nightly line profile changes, sometimes appearing as mirror-image events in the redshift and blueshift systems. The behavior of SS 433 is unprecedented

  6. Speed of light demonstration using Doppler beat

    Science.gov (United States)

    Bernal, Luis; Bilbao, Luis

    2018-05-01

    From an apparatus previously designed for measuring the Doppler shift using a rotating mirror, an improved, versatile version was developed for speed of light demonstrations in a classroom or a teaching laboratory. By adding a second detector and adequate beam-splitter and mirrors, three different configurations are easily assembled. One configuration is used for time-of-flight measurements between a near and a far detector, allowing one to measure the speed of light provided that the path length between detectors is known. Another variation is the interferometric method obtained by superposing the far and near signals in such a way that a minimum of the combined signal is obtained when the time delay makes the signals arrive out of phase by π radians. Finally, the standard Doppler configuration allows the measurement of the frequency beat as a function of the rotation frequency. The main advantages of the apparatus are (a) the experimental setup is simple and completely accessible to undergraduate students, (b) the light is visible, students can see the rays, which, with the use of appropriate screens, can be blocked at any point along their paths, (c) the experiment can take place entirely within the teaching laboratory or demonstration room (using the interferometric method, the shortest distance to the far mirror was as small as 0.5 m), and (d) different configurations can be built, including some economical setups within the budget of teaching laboratories.

  7. Parametric Investigation of Laser Doppler Microphones

    Science.gov (United States)

    Daoud, M.; Naguib, A.

    2002-11-01

    The concept of a Laser Doppler Microphone (LDM) is based on utilizing the Doppler frequency shift of a focused laser beam to measure the unsteady velocity of the center point of a flexible polymer diaphragm that is mounted on top of a hole and subjected to the unsteady pressure. Time integration of the velocity signal yields a time series of the diaphragm displacement, which can be converted to pressure from knowledge of the sensor's deflection sensitivity. In our APS/DFD presentation last year, the stringent frequency resolution requirement of these new sensors and methods to meet this requirement were discussed. Here, the dependence of the sensor characteristics (sensitivity, bandwidth, and noise floor) on various significant parameters is investigated in detail by calibrating the sensor in a plane wave tube in the frequency range of 50 - 5000 Hz. Parameters investigated include sensor diaphragm material and thickness, sensor size, damping of the diaphragm motion and laser beam spot size. The results shed light on the operating limits of the new sensor and demonstrate its ability to conduct high-spatial-resolution measurements in typical high-Reynolds-number test facilities. Moreover, calibrated LDM sensors were used to conduct measurements in a separating/reattaching flow and the results are compared to classical electret-type microphones with a similar sensing diameter.

  8. Laser doppler velocimetry and confined flows

    Directory of Open Access Journals (Sweden)

    Ilić Jelena T.

    2017-01-01

    Full Text Available Finding the mode, in which two component laser Doppler velocimetry can be applied to flows confined in cylindrical tubes or vessels, was the aim of this study. We have identified principle issues that influence the propagation of laser beams in laser Doppler velocimetry system, applied to flow confined in cylindrical tube. Among them, the most important are influences of fluid and wall refractive indices, wall thickness and internal radius ratio and beam intersection angle. In analysis of the degrees of these influences, we have applied mathematical model, based on geometrical optics. The separation of measurement volumes, that measure different velocity components, has been recognized as the main drawback. To overcome this, we propose a lens with dual focal length – primary focal length for the measurement of one velocity component and secondary focal length for the measurement of the other velocity component. We present here the procedure for calculating the optimal value of secondary focal length, depending on experimental set-up parameters. The mathematical simulation of the application of the dual focal length lens, for chosen cases presented here, confirmed the accuracy of the proposed procedure.

  9. Color Doppler Ultrasonographic Features of Hashimoto's Thyroiditis

    International Nuclear Information System (INIS)

    Lee, Joo Hyuk; Kim, Mie Young; Rho, Eun Jin; Yi, Jeong Geun; Han, Chun Hwan; Hwang, Hee Yong

    1995-01-01

    Color Doppler ultrasonographic(US) features of 28 patients with Hashimato's thyroiditis were evaluated with regard to echo and color-flow patterns. Correlation of color-flow pattern with thyroid function was performed. All 28 patients showed varying degrees of diffuse enlargement of the thyroid gland and a heterogeneous echo pattern.Color-flow pattern of increased blood flow. Low to moderate, focally increased blood flow was seen in 26 patients(92.8%). Of these 26 patients, 24 patients showed subclinical hypothyroidism or euthyroidism. Two patients who showed hyperthyroidism showed several pieces of focally increased color flow, Which was noted during both systole and diastole. Diffuse, multifocal color-flow throughout thyroid gland was seen in two patients with Hashimato's thyroiditis: one with clinical hypothyroidism and the other with subclinical hypothyroidism. Even though Hashimoto's thyroiditis showed variable color-flow patterns, we believe that heterogenous parenchymal echopattern with low or moderately increased flow is a rather characteristic feature of Hashimoto's thyroiditis, and we suggest that color Doppler US provides additional information for evaluation of Hashimoto's thyroiditis

  10. Is Doppler ultrasound useful for evaluating gestational trophoblastic disease?

    Directory of Open Access Journals (Sweden)

    Lawrence H. Lin

    Full Text Available Doppler ultrasound is a non-invasive method for evaluating vascularization and is widely used in clinical practice. Gestational trophoblastic neoplasia includes a group of highly vascularized malignancies derived from placental cells. This review summarizes data found in the literature regarding the applications of Doppler ultrasound in managing patients with gestational trophoblastic neoplasia. The PubMed/Medline, Web of Science, Cochrane and LILACS databases were searched for articles published in English until 2014 using the following keywords: “Gestational trophoblastic disease AND Ultrasonography, Doppler.” Twenty-eight articles met the inclusion criteria and were separated into the 4 following groups according to the aim of the study. (1 Doppler ultrasound does not seem to be capable of differentiating partial from complete moles, but it might be useful when evaluating pregnancies in which a complete mole coexists with a normal fetus. (2 There is controversy in the role of uterine artery Doppler velocimetry in the prediction of development of gestational trophoblastic neoplasia. (3 Doppler ultrasound is a useful tool in the diagnosis of gestational trophoblastic neoplasia because abnormal myometrial vascularization and lower uterine artery Doppler indices seem to be correlated with invasive disease. (4 Lower uterine artery Doppler indices in the diagnosis of gestational trophoblastic neoplasia are associated with methotrexate resistance and might play a role in prognosis. CONCLUSION: Several studies support the importance of Doppler ultrasound in the management of patients with gestational trophoblastic neoplasia, particularly the role of Doppler velocimetry in the prediction of trophoblastic neoplasia and the chemoresistance of trophoblastic tumors. Doppler findings should be used as ancillary tools, along with human chorionic gonadotropin assessment, in the diagnosis of gestational trophoblastic neoplasia.

  11. Is Doppler ultrasound useful for evaluating gestational trophoblastic disease?

    Science.gov (United States)

    Lin, Lawrence H; Bernardes, Lisandra S; Hase, Eliane A; Fushida, Koji; Francisco, Rossana P V

    2015-12-01

    Doppler ultrasound is a non-invasive method for evaluating vascularization and is widely used in clinical practice. Gestational trophoblastic neoplasia includes a group of highly vascularized malignancies derived from placental cells. This review summarizes data found in the literature regarding the applications of Doppler ultrasound in managing patients with gestational trophoblastic neoplasia. The PubMed/Medline, Web of Science, Cochrane and LILACS databases were searched for articles published in English until 2014 using the following keywords: "Gestational trophoblastic disease AND Ultrasonography, Doppler." Twenty-eight articles met the inclusion criteria and were separated into the 4 following groups according to the aim of the study. (1) Doppler ultrasound does not seem to be capable of differentiating partial from complete moles, but it might be useful when evaluating pregnancies in which a complete mole coexists with a normal fetus. (2) There is controversy in the role of uterine artery Doppler velocimetry in the prediction of development of gestational trophoblastic neoplasia. (3) Doppler ultrasound is a useful tool in the diagnosis of gestational trophoblastic neoplasia because abnormal myometrial vascularization and lower uterine artery Doppler indices seem to be correlated with invasive disease. (4) Lower uterine artery Doppler indices in the diagnosis of gestational trophoblastic neoplasia are associated with methotrexate resistance and might play a role in prognosis. Several studies support the importance of Doppler ultrasound in the management of patients with gestational trophoblastic neoplasia, particularly the role of Doppler velocimetry in the prediction of trophoblastic neoplasia and the chemoresistance of trophoblastic tumors. Doppler findings should be used as ancillary tools, along with human chorionic gonadotropin assessment, in the diagnosis of gestational trophoblastic neoplasia.

  12. Tratamento da recidiva hemorrágica por varizes do esôfago em doentes esquistossomóticos operados Treatment of recurrent hemorrhage esophageal varices in schistosomotic patients after surgery

    Directory of Open Access Journals (Sweden)

    José Cesar Assef

    2003-01-01

    Full Text Available OBJETIVO: Padronizar o tratamento da recidiva hemorrágica por varizes do esôfago em esquistossomóticos, após operações não-derivativas. MÉTODOS: Tratamos 45 doentes esquistossomóticos que apresentaram recidiva hemorrágica por varizes do esôfago. Realizamos ultra-sonografia abdominal, e, estudos angiográficos constituindo-se dois grupos: Grupo A - Dezenove doentes (42,2% com ausência do baço, artéria esplênica ocluída e artéria e veia gástricas esquerdas pérvias, caracterizando a esplenectomia na operação anterior. Grupo B - Vinte e seis doentes (57,8% com imagem esplênica ausente, artérias esplênica e gástrica esquerda ocluídas e veia gástrica esquerda não-opacificada, evidenciando esplenectomia e alguma forma de desvascularização gastroesofágica praticadas anteriormente. Os doentes do Grupo A foram reoperados para executar a desvascularização gastroesofágica e os do Grupo B, submetidos a programa de escleroterapia endoscópica. RESULTADOS: No Grupo A, um paciente (5,3% apresentou recidiva hemorrágica no pós-operatório tardio. Na avaliação endoscópica final, as varizes esofágicas diminuíram, em número ou calibre, em 14 doentes (73,7%, desapareceram em três (15,8% e em dois (10,5%, permaneceram inalteradas. No Grupo B, seis pacientes (23,1% apresentaram recidiva do sangramento, controlada em quatro deles e em dois, que persistiram com sangramento praticou-se a derivação mesentérico-cava e ambos morreram. Na última avaliação endoscópica, as varizes esofágicas desapareceram em 17 doentes (65,4%, reduziram o número ou calibre em sete (26,9% e, em dois (7,7%, permaneceram inalteradas. CONCLUSÕES: 1 A desvacularização gastroesofágica é adequada para os doentes esplenectomizados, com a artéria e a veia gástricas esquerdas pérvias. 2 Um programa de longa duração de escleroterapia endoscópica das varizes do esôfago pode ser uma opção para os doentes esplenectomizados, com a artéria g

  13. The effectiveness of Doppler controlled hemorrhoidal artery ligation ...

    African Journals Online (AJOL)

    In this work, we discuss the preliminary results of the effectiveness of the hemorrhoidal artery ligation under control Doppler as a new technique for the treatment of hemorrhoids. We report the results of patients with hemorrhoids we have followed over a period of one year who were treated with HAL Doppler. The intra-and ...

  14. Musculoskeletal colour/power Doppler in sports medicine

    DEFF Research Database (Denmark)

    Boesen, M I; Boesen, M; Langberg, Henning

    2010-01-01

    This review article discusses the aspects of sports medicine where musculoskeletal Doppler ultrasound has valuable contribution in diagnosis and/or treatment of some of the typical musculoskeletal sports injuries. Also, conditions where the Doppler ultrasound has no value are discussed. Some...

  15. 21 CFR 892.1550 - Ultrasonic pulsed doppler imaging system.

    Science.gov (United States)

    2010-04-01

    ... system. (a) Identification. An ultrasonic pulsed doppler imaging system is a device that combines the... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultrasonic pulsed doppler imaging system. 892.1550... include signal analysis and display equipment, patient and equipment supports, component parts, and...

  16. Micro-Doppler classification of riders and riderless horses

    Science.gov (United States)

    Tahmoush, David

    2014-05-01

    Micro-range Micro-Doppler can be used to isolate particular parts of the radar signature, and in this case we demonstrate the differences in the signature between a walking horse versus a walking horse with a rider. Using micro-range micro-Doppler, we can distinguish the radar returns from the rider as separate from the radar returns of the horse.

  17. Correlation between Spectral Index and Doppler Factor for a ...

    Indian Academy of Sciences (India)

    Abstract. Relativistic beaming effect is important for blazars. In a very recent work, γ-ray Doppler factors were calculated for a sample of Fermi blazars (Fan et al. 2013). In this work, we investigated the correlation between the Doppler factor and the effective spectral index, αOX, and found an anticorrelation between them.

  18. Compressive sensing for high resolution profiles with enhanced Doppler performance

    NARCIS (Netherlands)

    Anitori, L.; Hoogeboom, P.; Chevalier, F. Le; Otten, M.P.G.

    2012-01-01

    In this paper we demonstrate how Compressive Sensing (CS) can be used in pulse-Doppler radars to improve the Doppler performance while preserving range resolution. We investigate here two types of stepped frequency waveforms, the coherent frequency bursts and successive frequency ramps, which can be

  19. Comparison between Doppler Ultrasound and Biopsy Findings in ...

    African Journals Online (AJOL)

    Methods: We retrospectively studied a random sample of 188 kidney transplanted patients who had Doppler-ultrasound examination followed within two weeks by transplant biopsy. We evaluated the specificity and sensitivity of Doppler ultrasound in diagnosing rejection at different RI thresholds, using the reported biopsy ...

  20. ASPECTOS ULTRA-SONOGRÁFICOS DA ESQUISTOSSOMOSE HEPATOESPLÊNICA Ultrasound findings in hepatosplenic schistosomiasis

    Directory of Open Access Journals (Sweden)

    Márcio Martins Machado

    2002-01-01

    Full Text Available A ultra-sonografia representa uma importante contribuição no diagnóstico da forma hepatoesplênica da esquistossomose. A ultra-sonografia permite a identificação das principais alterações, como espessamento periportal, perivesicular, aumento do lobo hepático esquerdo, redução do lobo hepático direito e esplenomegalia. Adicionalmente, os padrões hemodinâmicos podem ser avaliados com o Doppler, sendo possível a análise das veias porta, mesentérica superior e esplênica, além de facilitar o estudo dos vasos venosos colaterais. Em áreas endêmicas, a ultra-sonografia assume papel de destaque, sendo superior à avaliação clínica na identificação da hepatoesplenomegalia e possibilitando o acompanhamento dos pacientes submetidos a tratamento clínico. Neste trabalho, os autores apresentam uma revisão dos principais achados sonográficos e ao Doppler da esquistossomose hepatoesplênica, sendo demonstrada, também, a relação destes achados com os aspectos clínico-patológicos desta doença.Ultrasound represents an important contribution to the diagnosis of hepatosplenic mansonic schistosomiasis. Abnormalities such as hyperechoic fibrotic bands along the portal vessels, volumetric reduction of the right hepatic lobe, enlargement of the left lobe, perivesicular fibrotic thickening and splenomegaly can be recognized. Moreover, the hemodynamic status of the portal venous system may also be evaluated by Doppler analysis, including the identification of collateral veins and portosystemic venous shunts. In endemic areas, ultrasound is of great value in the identification of hepatosplenomegaly, allowing follow-up of patients under clinical treatment. This review presents the ultrasonographic and Doppler features of hepatosplenic schistosomiasis. The relationship between these findings and the clinical and pathological characteristics of this disease are also discussed.

  1. Analysis of Doppler effect with JAERI-Fast set

    International Nuclear Information System (INIS)

    Takano, Hideki; Matsui, Yasushi.

    1977-07-01

    Temperature dependence of group cross sections in the JAERI-Fast set versions I, IR, II and IIR has been tested from the analysis of Doppler experiments performed with two different methods. One is Doppler reactivity measurement for the whole core of SEFOR assembly, and the other sample Doppler reactivity measurement for natural UO 2 in FCA assemblies V-1, V-2, VI-1 and VI-2, ZPR-6-7, ZPR-3-47, and ZPPR-2 and 3. Doppler effects were calculated with one- and two-dimensional diffusion 1-st order perturbation code DOPP2D. The results calculated with the JAERI-Fast set versions II and IIR are in good agreement with the experimental ones. In these calculation, resonance heterogeneity effect, stainless-stell buffer effect and plate heterogeneity effect are considered, and these effects contribute significantly to Doppler effect. (auth.)

  2. High-Frame-Rate Power Doppler Ultrasound Is More Sensitive than Conventional Power Doppler in Detecting Rheumatic Vascularisation

    NARCIS (Netherlands)

    M. van der Ven (Myrthe); J.J. Luime (Jolanda); van der Velden, L.L. (Levinia L.); J.G. Bosch (Hans); J.M.W. Hazes (Mieke); H.J. Vos (Rik)

    2016-01-01

    textabstractEarly recognition of joint inflammation will increase treatment efficacy in rheumatoid arthritis (RA). Yet, conventional power Doppler (PD) ultrasound might not be sufficiently sensitive to detect minor inflammation. We investigated the sensitivity of high-frame rate Doppler, combined

  3. Doppler time-of-flight imaging

    KAUST Repository

    Heidrich, Wolfgang

    2017-02-16

    Systems and methods for imaging object velocity are provided. In an embodiment, at least one Time-of-Flight camera is used to capture a signal representative of an object in motion over an exposure time. Illumination and modulation frequency of the captured motion are coded within the exposure time. A change of illumination frequency is mapped to measured pixel intensities of the captured motion within the exposure time, and information about a Doppler shift in the illumination frequency is extracted to obtain a measurement of instantaneous per pixel velocity of the object in motion. The radial velocity information of the object in motion can be simultaneously captured for each pixel captured within the exposure time. In one or more aspects, the illumination frequency can be coded orthogonal to the modulation frequency of the captured motion. The change of illumination frequency can correspond to radial object velocity.

  4. Gamma-ray induced doppler broadening

    International Nuclear Information System (INIS)

    Robinson, S.J.

    1992-01-01

    The ultra high resolving power of the GAMS4 double-flat crystal spectrometer (M.S. Dewey et al Nucl. Instrum. Methods A 284 (1989) 151.) has been used to observe the Doppler broadening of gamma-rays emitted by nuclei recoiling at speeds as low as 10 -6 c. Such recoils may be induced by the previous emission of gamma-radiation following thermal neutron capture. If the population mechanism of an excited state is known (or can be approximated) and the slowing down mechanism can be modeled, then this technique can be used to extract the lifetime of excited nuclear states. The combination of this technique and the neutron capture reaction allows the study of states which cannot necessarily be accessed by other means. This has allowed the resolution of a number of long standing questions in low-spin nuclear structure. The basis of the technique is discussed and a number of examples given

  5. Phase Doppler anemometry as an ejecta diagnostic

    Science.gov (United States)

    Bell, D. J.; Chapman, D. J.

    2017-01-01

    When a shock wave is incident on a free surface, micron sized pieces of the material can be ejected from that surface. Phase Doppler Anemometry (PDA) is being developed to simultaneously measure the sizes and velocities of the individual shock induced ejecta particles; providing an important insight into ejecta phenomena. The results from experiments performed on the 13 mm bore light gas gun at the Institute of Shock Physics, Imperial College London are presented. Specially grooved tin targets were shocked at pressures of up to 14 GPa, below the melt on release pressure, to generate ejecta particles. These experiments are the first time that PDA has been successfully fielded on dynamic ejecta experiments. The results and current state of the art of the technique are discussed along with the future improvements required to optimise performance and increase usability.

  6. Doppler interpretation of quasar red shifts.

    Science.gov (United States)

    Zapolsky, H S

    1966-08-05

    The hypothesis that the quasistellar sources (quasars) are local objects moving with velocities close to the speed of light is examined. Provided there is no observational cutoff on apparent bolometric magnitude for the quasars, the transverse Doppler effect leads to the expectation of fewer blue shifts than red shifts for an isotropic distribution of velocities. Such a distribution also yields a function N(z), the number of objects with red shift less than z which is not inconsistent with the present data. On the basis of two extreme assumptions concerning the origin of such rapidly moving sources, we computed curves of red shift plotted against magnitude. In particular, the curve obtained on the assumption that the quasars originated from an explosion in or nearby our own galaxy is in as good agreement with the observations as the curve of cosmological red shift plotted against magnitude.

  7. Microscale Heat Conduction Models and Doppler Feedback

    International Nuclear Information System (INIS)

    Hawari, Ayman I.; Ougouag, Abderrafi

    2015-01-01

    The objective of this project is to establish an approach for providing the fundamental input that is needed to estimate the magnitude and time-dependence of the Doppler feedback mechanism in Very High Temperature reactors. This mechanism is the foremost contributor to the passive safety of gas-cooled, graphite-moderated high temperature reactors that use fuel based on Tristructural-Isotropic (TRISO) coated particles. Therefore, its correct prediction is essential to the conduct of safety analyses for these reactors. Since the effect is directly dependent on the actual temperature reached by the fuel during transients, the underlying phenomena of heat deposition, heat transfer and temperature rise must be correctly predicted. To achieve the above objective, this project will explore an approach that accounts for lattice effects as well as local temperature variations and the correct definition of temperature and related local effects.

  8. Ultrasonic intrusion sensor using the Doppler effect; Choonpa Doppler hoshiki shinnyu sensor

    Energy Technology Data Exchange (ETDEWEB)

    Kani, H; Iwasaki, N; Goto, M [Nippon Soken, Inc., Tokyo (Japan); Tsuzuki, T; Nakamura, T [Denso Corp., Aichi (Japan)

    1997-10-01

    For vehicle anti-theft alarm systems which cope with vehicle and car component theft, EU initiated vehicle security regulations from Jan 1997. Also, the insurance industry has instituted the insurance certification of vehicle anti-theft alarm systems. We have developed an ultrasonic intrusion sensor using the doppler effect for vehicle anti-theft alarm systems specifically for these EU regulations and insurance certification. 2 refs., 7 figs., 1 tab.

  9. Laser Doppler flowmetry in endodontics: a review.

    Science.gov (United States)

    Jafarzadeh, H

    2009-06-01

    Vascular supply is the most accurate marker of pulp vitality. Tests for assessing vascular supply that rely on the passage of light through a tooth have been considered as possible methods for detecting pulp vitality. Laser Doppler flowmetry (LDF), which is a noninvasive, objective, painless, semi-quantitative method, has been shown to be reliable for measuring pulpal blood flow. The relevant literature on LDF in the context of endodontics up to March 2008 was reviewed using PubMed and MEDLINE database searches. This search identified papers published between June 1983 and March 2008. Laser light is transmitted to the pulp by means of a fibre optic probe. Scattered light from moving red blood cells will be frequency-shifted whilst that from the static tissue remains unshifted. The reflected light, composed of Doppler-shifted and unshifted light, is returned by afferent fibres and a signal is produced. This technique has been successfully employed for estimating pulpal vitality in adults and children, differential diagnosis of apical radiolucencies (on the basis of pulp vitality), examining the reactions to pharmacological agents or electrical and thermal stimulation, and monitoring of pulpal responses to orthodontic procedures and traumatic injuries. Assessments may be highly susceptible to environmental and technique-related factors. Nonpulpal signals, principally from periodontal blood flow, may contaminate the signal. Because this test produces no noxious stimuli, apprehensive or distressed patients accept it more readily than current methods of pulp vitality assessment. A review of the literature and a discussion of the application of this system in endodontics are presented.

  10. Electrocardiografo por computadora

    OpenAIRE

    Tinoco Hernandez, Rosanna; Paredes Bejarano, Margarita; Romero Chaglia, Norman; Yapur Auad, Miguel Eduardo

    2009-01-01

    El presente trabajo trata sobrees el diseño y la implementación de un graficador de señales cardiacas por computadora, para lo cual diseñamos un circuito electrónico capaz de recibir la senal analógica proveniente de la actividad electrica del corazón , amplificarla, y luego convertirla en una señal digital para ser procesada por software y finalmente ser graficada, siendo posible así observar la señal cardiaca en el monitor de un computador como un tren de pulsos. Cabe destacar que par...

  11. Use of Doppler ultrasound for non-invasive urodynamic diagnosis

    Directory of Open Access Journals (Sweden)

    Hideo Ozawa

    2009-01-01

    Full Text Available Objectives: A totally non-invasive transperineal urodynamic technique using Doppler ultrasonography has been developed. Methods: Since normal urine does not have blood cells, urine was thought not to produce the Doppler effects. However, basic studies confirmed that the decrease of pressure at high velocity (Bernouilli effect caused dissolved gas to form microbubbles, which are detected by Doppler ultrasonography. Subjects sat and the probe was advanced via remote control to achieve gentle contact with the perineal skin. The digital uroflow data signals and the color Doppler ultrasound video images were processed on a personal computer. The flow-velocity curves from two sites; the distal prostatic urethra just above the external sphincter (V1 and the sphincteric urethra (V2 were plotted against time. The parameters of both the pressure-flow studies and the Doppler ultrasound urodynamic studies were compared in men who had various degrees of obstruction. Results: Functional cross-sectional area at prostatic urethra (A1, calculated by Q max /V1, was lower in the group of bladder outlet obstruction (BOO vs. control group. Velocity ratio (VR, which was calculated by V1/V2, was the parameter having the best correlation with BOO index, though A1 had a similar correlation. This method is viable to diagnose the degree of BOO. Conclusions: The development of non-invasive Doppler ultrasound videourodynamics (Doppler UDS will dramatically expand the information on voiding function.

  12. Índice orientador do tratamento sistêmico da gravidez ectópica íntegra com dose única de metotrexato Index for the systemic treatment of unruptured ectopic pregnancy with a single dose of methotrexate

    Directory of Open Access Journals (Sweden)

    Julio Elito Junior

    1998-04-01

    Full Text Available Foi realizado estudo longitudinal em 42 pacientes com diagnóstico de gravidez ectópica íntegra, com o intuito de se elaborar um índice orientador do uso sistêmico de metotrexato em dose única (50 mg/m² por via intramuscular. O acompanhamento se fez através de dosagens de beta-hCG (fração beta do hormônio gonadotrópico coriônico realizadas no 1º, 4º e 7º dias após o emprego do quimioterápico. Quando ocorreu queda de 15% ou mais nos títulos de beta-hCG, apurados no 4º e no 7º dia, as pacientes receberam alta hospitalar e seguimento ambulatorial com dosagens semanais de beta-hCG até que se atingissem níveis inferiores a 5 mUI/ml. Foi elaborado um índice orientador do tratamento sistêmico com metotrexato baseado nos seguintes parâmetros: (1 valores iniciais de beta-hCG; (2 aspecto da imagem à ultra-sonografia (hematossalpinge, anel tubário, embrião vivo; (3 maior diâmetro da massa anexial; (4 quantidade de líquido livre; (5 fluxo vascular medido por meio do doppler colorido. Cada parâmetro recebeu pontuação de 0 a 2. A nota zero significa elemento de mau prognóstico, a nota dois indica parâmetros favoráveis e a nota um, situações intermediárias. O índice de sucesso com dose única foi de 69,0% (29/42 pacientes. A ultra-sonografia transvaginal com doppler colorido foi realizada em 20 das 42 pacientes do estudo. Neste grupo de 20 pacientes o sucesso do tratamento ocorreu em 75,0% dos casos (15/20. Entre as 22 pacientes que não foram avaliadas com doppler colorido a média das notas do índice nos casos de sucesso foi de 6,6, nas de insucesso 3,1. No grupo de pacientes avaliadas por doppler (20 pacientes as médias foram de 7,9 (sucesso e 4,2 (fracasso. No presente estudo a nota de corte foi estabelecida levando-se em conta o valor abaixo do qual o tratamento não foi efetivo e correspondeu a cinco, pois 93,75% das pacientes com nota superior a 5 evoluíram com sucesso (15/16, ao passo que notas inferiores ou

  13. O uso da ressonância magnética na investigação do câncer mamário Magnetic resonance imaging in the evaluation of breast cancer

    Directory of Open Access Journals (Sweden)

    Beatriz Regina Alvares

    2003-12-01

    Full Text Available Os métodos diagnósticos de imagem mamografia, ultra-sonografia e cintilografia são exames imprescindíveis no diagnóstico do câncer de mama e no acompanhamento após o procedimento cirúrgico, porém, todos apresentam limitações específicas. Atualmente, a ressonância magnética tem-se revelado um método diagnóstico promissor para avaliar mais detalhadamente lesões tumorais do parênquima mamário. Neste trabalho os autores descrevem as principais indicações e os achados da ressonância magnética no câncer de mama, bem como comparam o seu desempenho com o dos outros métodos de imagem - mamografia, ultra-sonografia e cintilografia -, incluindo as vantagens e limitações de cada modalidade.Mammography, ultrasonography and scintimammography are essential examinations for the diagnosis and post-surgical follow-up of patients with breast cancer, although all these modalities may present specific limitations. In recent years magnetic resonance imaging has demonstrated good performance in detecting breast tumors in the mammary gland. In this study the authors describe the magnetic resonance imaging main indications and findings in patients with breast cancer, and compare the performance of mammography, ultrasonography and scintimammography, including the advantages and limitations of each modality.

  14. Indice por Materias

    Directory of Open Access Journals (Sweden)

    Montoya H Luz Marina

    1982-09-01

    Full Text Available Un índice es una lista de palabras o frases indicadores asociados que permite la ubicación de material al interior de un libro o una publicación, en este caso será por el nombre de la materia.

  15. Sub-Doppler laser cooling of potassium atoms

    Energy Technology Data Exchange (ETDEWEB)

    Landini, M. [LENS and Dipartimento di Fisica e Astronomia, Universita di Firenze, I-50019 Sesto Fiorentino (Italy); INFN, Sezione di Firenze, I-50019 Sesto Fiorentino (Italy); Dipartimento di fisica, Universita di Trento, I-38123 Povo (Trento) (Italy); Roy, S.; Carcagni, L.; Trypogeorgos, D. [LENS and Dipartimento di Fisica e Astronomia, Universita di Firenze, I-50019 Sesto Fiorentino (Italy); Fattori, M.; Inguscio, M.; Modugno, G. [LENS and Dipartimento di Fisica e Astronomia, Universita di Firenze, I-50019 Sesto Fiorentino (Italy); INFN, Sezione di Firenze, I-50019 Sesto Fiorentino (Italy)

    2011-10-15

    We investigate the sub-Doppler laser cooling of bosonic potassium isotopes, whose small hyperfine splitting has so far prevented cooling below the Doppler temperature. We find instead that the combination of a dark optical molasses scheme that naturally arises in this kind of system and an adiabatic ramping of the laser parameters allows us to reach sub-Doppler temperatures for small laser detunings. We demonstrate temperatures as low as 25{+-}3 {mu}K and 47{+-}5 {mu}K in high-density samples of the two isotopes {sup 39}K and {sup 41}K, respectively. Our findings should find application to other atomic systems.

  16. Sub-Doppler laser cooling of potassium atoms

    International Nuclear Information System (INIS)

    Landini, M.; Roy, S.; Carcagni, L.; Trypogeorgos, D.; Fattori, M.; Inguscio, M.; Modugno, G.

    2011-01-01

    We investigate the sub-Doppler laser cooling of bosonic potassium isotopes, whose small hyperfine splitting has so far prevented cooling below the Doppler temperature. We find instead that the combination of a dark optical molasses scheme that naturally arises in this kind of system and an adiabatic ramping of the laser parameters allows us to reach sub-Doppler temperatures for small laser detunings. We demonstrate temperatures as low as 25±3 μK and 47±5 μK in high-density samples of the two isotopes 39 K and 41 K, respectively. Our findings should find application to other atomic systems.

  17. Acidente vascular cerebral e outras complicações do sistema nervoso central nas doenças falciformes Stroke and other vascular complications of the central nervous system in sickle cell disease

    Directory of Open Access Journals (Sweden)

    Ivan L. Angulo

    2007-09-01

    Full Text Available A principal complicação da doença falciforme na infância é a das artérias cerebrais, mas após os 20 anos também pode se manifestar, como seqüela de lesões anteriores ou neoformadas. A vasculopatia tem a maior importância no desenvolvimento da criança e na qualidade de vida. Além do acidente vascular cerebral completo ou incompleto ("silencioso", existem outras complicações do sistema nervoso central, porém não exclusivas. O diagnóstico da vasculopatia cerebral falciforme necessita auxílio neurorradiológico. O tratamento se faz basicamente com transfusões de eritrócitos contendo hemoglobina A. O objetivo deste trabalho é rever a literatura médica, procurando selecionar a melhor conduta em diagnóstico e tratamento que seja possível empregar de imediato, para reduzir a morbidade e mortalidade da vasculopatia cerebral e elevar a qualidade de vida dos pacientes, principalmente na infância. Os fatores de risco clínicos e laboratoriais, incluindo a triagem por ultra-sonografia Doppler das artérias cerebrais e imagens de ressonância magnética, devem influenciar a decisão de instituir transfusões crônicas e a quelação do ferro transfusional deve acompanhar este tratamento.In children with sickle cell disease, cerebral arteries are prone to lesions that may cause deficiencies and poor quality of life. After the age of 20, new lesions may also occur. Besides stroke and silent cerebral ischemia, other lesions may occur. Radiologic images are necessary to diagnose and blood transfusions to treat. We reviewed the literature to choose best practices and guidelines to reduce morbidity and mortality and improve the quality of life of children with sickle cell disease. Risk factors identified from clinical and laboratory data and screening by Doppler ultrasonography and magnetic resonance must be used in order to make decisions about transfusion and iron chelation therapy.

  18. The Next Generation Airborne Polarimetric Doppler Radar

    Science.gov (United States)

    Vivekanandan, J.; Lee, Wen-Chau; Loew, Eric; Salazar, Jorge; Chandrasekar, V.

    2013-04-01

    NCAR's Electra Doppler radar (ELDORA) with a dual-beam slotted waveguide array using dual-transmitter, dual-beam, rapid scan and step-chirped waveform significantly improved the spatial scale to 300m (Hildebrand et al. 1996). However, ELDORA X-band radar's penetration into precipitation is limited by attenuation and is not designed to collect polarimetric measurements to remotely estimate microphysics. ELDORA has been placed on dormancy because its airborne platform (P3 587) was retired in January 2013. The US research community has strongly voiced the need to continue measurement capability similar to the ELDORA. A critical weather research area is quantitative precipitation estimation/forecasting (QPE/QPF). In recent years, hurricane intensity change involving eye-eyewall interactions has drawn research attention (Montgomery et al., 2006; Bell and Montgomery, 2006). In the case of convective precipitation, two issues, namely, (1) when and where convection will be initiated, and (2) determining the organization and structure of ensuing convection, are key for QPF. Therefore collocated measurements of 3-D winds and precipitation microphysics are required for achieving significant skills in QPF and QPE. Multiple radars in dual-Doppler configuration with polarization capability estimate dynamical and microphysical characteristics of clouds and precipitation are mostly available over land. However, storms over complex terrain, the ocean and in forest regions are not observable by ground-based radars (Bluestein and Wakimoto, 2003). NCAR/EOL is investigating potential configurations for the next generation airborne radar that is capable of retrieving dynamic and microphysical characteristics of clouds and precipitation. ELDORA's slotted waveguide array radar is not compatible for dual-polarization measurements. Therefore, the new design has to address both dual-polarization capability and platform requirements to replace the ELDORA system. NCAR maintains a C-130

  19. NAMMA NASA POLARIMETRIC DOPPLER WEATHER RADAR (NPOL) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The NAMMA NASA Polarimetric Doppler Weather Radar (NPOL) dataset used the NPOL, developed by a research team from Wallops Flight Facility, is a fully transportable...

  20. CAMEX-4 MIPS 915 MHZ DOPPLER WIND PROFILER V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The CAMEX-4 MIPS 915 MHZ Doppler Wind Profiler dataset was collected by the University of Alabama in Huntsville (UAH) Mobile Integrated Profiling System (MIPS),...

  1. [Postpartal ovarian thrombophlebitis. Value of Doppler ultrasonograph y].

    Science.gov (United States)

    Renaud-Giono, A; Giraud, J R; Poulain, P; Proudhon, J F; Grall, J Y; Moquet, P Y; Darnault, J P

    1996-01-01

    Thrombophlebitis of the ovarian vein is a well recognized but uncommon complication during the postpartum period. We report a small series and emphasize the contribution of color Doppler and the basic therapeutic measures.

  2. Doppler Wind Lidar Measurements and Scalability to Space

    Data.gov (United States)

    National Aeronautics and Space Administration — Global measurements of wind speed and direction from Doppler wind lidars, if available, would significantly improve forecasting of severe weather events such as...

  3. Nonlinear Suppression of Range Ambiguity in Pulse Doppler Radar

    National Research Council Canada - National Science Library

    Anderson, Jon

    2001-01-01

    ... ambiguities in Doppler and range. First introduced by Palermo in 1962 using two conjugate LFM pulses, the primary nonlinear suppression objective involves reducing range ambiguity, given the waveform is nominally unambiguous...

  4. Ambiguity Of Doppler Centroid In Synthetic-Aperture Radar

    Science.gov (United States)

    Chang, Chi-Yung; Curlander, John C.

    1991-01-01

    Paper discusses performances of two algorithms for resolution of ambiguity in estimated Doppler centroid frequency of echoes in synthetic-aperture radar. One based on range-cross-correlation technique, other based on multiple-pulse-repetition-frequency technique.

  5. The Doppler Effect: A Consideration of Quasar Redshifts.

    Science.gov (United States)

    Gordon, Kurtiss J.

    1980-01-01

    Provides information on the calculation of the redshift to blueshift ratio introduced by the transverse Doppler effect at relativistic speeds. Indicates that this shift should be mentioned in discussions of whether quasars are "local" rather than "cosmological" objects. (GS)

  6. Calculation of the Doppler broadening function using Fourier analysis

    International Nuclear Information System (INIS)

    Goncalves, Alessandro da Cruz

    2010-01-01

    An efficient and precise method for calculation of Doppler broadening function is very important to obtain average group microscopic cross sections, self shielding factors, resonance integrals and others reactor physics parameter. In this thesis two different methods for calculation of Doppler broadening function and interference term will be presented. The main method is based on a new integral form for Doppler broadening function ψ(x,ζ) which gives a mathematical interpretation of the approximation proposed by Bethe and Placzek, as the convolution of the Lorentzian function with a Gaussian function. This interpretation besides leading to a new integral form for ψ(x,ζ), enables to obtain a simple analytic solution for the Doppler broadening function. (author)

  7. CAMEX-4 MIPS 915 MHZ DOPPLER WIND PROFILER V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The University of Alabama in Huntsville (UAH) Mobile Integrated Profiling System (MIPS) is a mobile atmospheric profiling system. It includes a 915 MHz Doppler...

  8. A Prospective Study of Doppler Velocimetry in Pregnancy-induced ...

    African Journals Online (AJOL)

    Mubeen

    In umbilical artery Doppler, when S/D ratio was abnormal, ... count, differential count, erythrocyte sedimentation rate, hemoglobin percentage ... uric acid, VDRL tests, Hepatitis B surface antigen, HIV), ..... We are planning for a larger project in.

  9. Doppler electron velocimetry : notes on creating a practical tool.

    Energy Technology Data Exchange (ETDEWEB)

    Reu, Phillip L.; Milster, Tom (University of Arizona)

    2008-11-01

    The Doppler electron velocimeter (DEV) has been shown to be theoretically possible. This report attempts to answer the next logical question: Is it a practical instrument? The answer hinges upon whether enough electrons are available to create a time-varying Doppler current to be measured by a detector with enough sensitivity and bandwidth. The answer to both of these questions is a qualified yes. A target Doppler frequency of 1 MHz was set as a minimum rate of interest. At this target a theoretical beam current signal-to-noise ratio of 25-to-1 is shown for existing electron holography equipment. A detector is also demonstrated with a bandwidth of 1-MHz at a current of 10 pA. Additionally, a Linnik-type interferometer that would increase the available beam current is shown that would offer a more flexible arrangement for Doppler electron measurements over the traditional biprism.

  10. Methodology for obtaining wind gusts using Doppler lidar

    DEFF Research Database (Denmark)

    Suomi, Irene; Gryning, Sven-Erik; O'Connor, Ewan J.

    2017-01-01

    reduced the bias in the Doppler lidar gust factors from 0.07 to 0.03 and can be improved further to reduce the bias by using a realistic estimate of turbulence. Wind gust measurements are often prone to outliers in the time series, because they represent the maximum of a (moving-averaged) horizontal wind...... detection also outperformed the traditional Doppler lidar quality assurance method based on carrier-to-noise ratio, by removing additional unrealistic outliers present in the time series.......A new methodology is proposed for scaling Doppler lidar observations of wind gusts to make them comparable with those observed at a meteorological mast. Doppler lidars can then be used to measure wind gusts in regions and heights where traditional meteorological mast measurements are not available...

  11. Thermal Design for a Diffraction-Limited Doppler Spectrometer

    Data.gov (United States)

    National Aeronautics and Space Administration — The Univ. of Notre Dame is building a new high-resolution spectrometer named “iLocater” to achieve unprecedented radial velocity (RV) precision for stellar Doppler...

  12. ZEEMAN DOPPLER MAPS: ALWAYS UNIQUE, NEVER SPURIOUS?

    Energy Technology Data Exchange (ETDEWEB)

    Stift, Martin J.; Leone, Francesco [Armagh Observatory, College Hill, Armagh BT61 9DG (United Kingdom)

    2017-01-01

    Numerical models of atomic diffusion in magnetic atmospheres of ApBp stars predict abundance structures that differ from the empirical maps derived with (Zeeman) Doppler mapping (ZDM). An in-depth analysis of this apparent disagreement investigates the detectability by means of ZDM of a variety of abundance structures, including (warped) rings predicted by theory, but also complex spot-like structures. Even when spectra of high signal-to-noise ratio are available, it can prove difficult or altogether impossible to correctly recover shapes, positions, and abundances of a mere handful of spots, notwithstanding the use of all four Stokes parameters and an exactly known field geometry; the recovery of (warped) rings can be equally challenging. Inversions of complex abundance maps that are based on just one or two spectral lines usually permit multiple solutions. It turns out that it can by no means be guaranteed that any of the regularization functions in general use for ZDM (maximum entropy or Tikhonov) will lead to a true abundance map instead of some spurious one. Attention is drawn to the need for a study that would elucidate the relation between the stratified, field-dependent abundance structures predicted by diffusion theory on the one hand, and empirical maps obtained by means of “canonical” ZDM, i.e., with mean atmospheres and unstratified abundances, on the other hand. Finally, we point out difficulties arising from the three-dimensional nature of the atomic diffusion process in magnetic ApBp star atmospheres.

  13. Muscle activity characterization by laser Doppler Myography

    Science.gov (United States)

    Scalise, Lorenzo; Casaccia, Sara; Marchionni, Paolo; Ercoli, Ilaria; Primo Tomasini, Enrico

    2013-09-01

    Electromiography (EMG) is the gold-standard technique used for the evaluation of muscle activity. This technique is used in biomechanics, sport medicine, neurology and rehabilitation therapy and it provides the electrical activity produced by skeletal muscles. Among the parameters measured with EMG, two very important quantities are: signal amplitude and duration of muscle contraction, muscle fatigue and maximum muscle power. Recently, a new measurement procedure, named Laser Doppler Myography (LDMi), for the non contact assessment of muscle activity has been proposed to measure the vibro-mechanical behaviour of the muscle. The aim of this study is to present the LDMi technique and to evaluate its capacity to measure some characteristic features proper of the muscle. In this paper LDMi is compared with standard superficial EMG (sEMG) requiring the application of sensors on the skin of each patient. sEMG and LDMi signals have been simultaneously acquired and processed to test correlations. Three parameters has been analyzed to compare these techniques: Muscle activation timing, signal amplitude and muscle fatigue. LDMi appears to be a reliable and promising measurement technique allowing the measurements without contact with the patient skin.

  14. Muscle activity characterization by laser Doppler Myography

    International Nuclear Information System (INIS)

    Scalise, Lorenzo; Casaccia, Sara; Marchionni, Paolo; Ercoli, Ilaria; Tomasini, Enrico Primo

    2013-01-01

    Electromiography (EMG) is the gold-standard technique used for the evaluation of muscle activity. This technique is used in biomechanics, sport medicine, neurology and rehabilitation therapy and it provides the electrical activity produced by skeletal muscles. Among the parameters measured with EMG, two very important quantities are: signal amplitude and duration of muscle contraction, muscle fatigue and maximum muscle power. Recently, a new measurement procedure, named Laser Doppler Myography (LDMi), for the non contact assessment of muscle activity has been proposed to measure the vibro-mechanical behaviour of the muscle. The aim of this study is to present the LDMi technique and to evaluate its capacity to measure some characteristic features proper of the muscle. In this paper LDMi is compared with standard superficial EMG (sEMG) requiring the application of sensors on the skin of each patient. sEMG and LDMi signals have been simultaneously acquired and processed to test correlations. Three parameters has been analyzed to compare these techniques: Muscle activation timing, signal amplitude and muscle fatigue. LDMi appears to be a reliable and promising measurement technique allowing the measurements without contact with the patient skin

  15. Hydronephrosis and pregnancy: study with Doppler echography

    International Nuclear Information System (INIS)

    Ripolles Gonzalez, T.R.; Ambit Capdevilla, S.; Sanguesa Nebot, C.; Lazaro, S. de; Garcia Vila, J.H.; Belloch Ugarte, V.

    1993-01-01

    An 18-month study was performed to establish the normal intrarenal resistance index during pregnancy, in order to determine whether it differed significantly depending on the week of gestation or the degree of hydronephrosis. For this purpose , the flow velocity waves obtained in right kidney were analyzed in a group of 112 patients on the basis of 209 explorations. The kidneys were classified as grade 0,I,II, or III according to the degree of hydronephrosis. Doppler signal sampling was carried out at the level of the corticomedullary junction. From the results of the study it can be deduced that the index of intrarenal resistance during pregnancy is similar to that of the general population, that there are no significant differences among the groups with different degree of hydronephrosis and that the index does not vary according to the different weeks of gestation. These findings suggest that, during pregnancy, a pathological resistance index in a kidney should not be attributed to the physiological changes associated with normal gestation. (Author) 21 refs

  16. Doppler time-of-flight imaging

    KAUST Repository

    Heide, Felix

    2015-07-30

    Over the last few years, depth cameras have become increasingly popular for a range of applications, including human-computer interaction and gaming, augmented reality, machine vision, and medical imaging. Many of the commercially-available devices use the time-of-flight principle, where active illumination is temporally coded and analyzed on the camera to estimate a per-pixel depth map of the scene. In this paper, we propose a fundamentally new imaging modality for all time-of-flight (ToF) cameras: per-pixel velocity measurement. The proposed technique exploits the Doppler effect of objects in motion, which shifts the temporal frequency of the illumination before it reaches the camera. Using carefully coded illumination and modulation frequencies of the ToF camera, object velocities directly map to measured pixel intensities. We show that a slight modification of our imaging system allows for color, depth, and velocity information to be captured simultaneously. Combining the optical flow computed on the RGB frames with the measured metric axial velocity allows us to further estimate the full 3D metric velocity field of the scene. We believe that the proposed technique has applications in many computer graphics and vision problems, for example motion tracking, segmentation, recognition, and motion deblurring.

  17. Apendicitis por Paracoccidioides brasiliensis

    Directory of Open Access Journals (Sweden)

    Ana Beatriz MUÑOZ URRIBARRI

    2006-01-01

    Full Text Available La paracoccidioidomicosis es la micosis más prevalente en Sudamérica. La forma aguda afecta el sistema fagocítico mononuclear de niños y personas inmunocomprometidas. El compromiso gastrointestinal es frecuente y su patogenia implica diseminación hematógena y linfática. La linfadenomegalia abdominal causa obstrucción intestinal y abdomen agudo. En este artículo damos a conocer el caso de un niño con compromiso gastrointestinal por apendicitis. Este es el primer caso reportado de apendicitis por esta patología. (Rev Med Hered 2006;17:58-60.

  18. Optimized variational analysis scheme of single Doppler radar wind data

    Science.gov (United States)

    Sasaki, Yoshi K.; Allen, Steve; Mizuno, Koki; Whitehead, Victor; Wilk, Kenneth E.

    1989-01-01

    A computer scheme for extracting singularities has been developed and applied to single Doppler radar wind data. The scheme is planned for use in real-time wind and singularity analysis and forecasting. The method, known as Doppler Operational Variational Extraction of Singularities is outlined, focusing on the principle of local symmetry. Results are presented from the application of the scheme to a storm-generated gust front in Oklahoma on May 28, 1987.

  19. Numerical stud of glare spot phase Doppler anemometry

    OpenAIRE

    Hespel , Camille; Ren , Kuan Fang; Gréhan , Gérard; Onofri , Fabrice

    2008-01-01

    International audience; The phase Doppler anemometry has (PDA) been developed to measure simultaneously the velocity and the size of droplets. When the concentration of particles is high, tightly focused beams must be used, as in the dual burst PDA. The latter permits an access to the refractive index of the particle, but the effect of wave front curvature of the incident beams becomes evident. In this paper, we introduce a glare spot phase Doppler anemometry which uses two large beams. The i...

  20. Laser Doppler measurements in two-phase flows

    International Nuclear Information System (INIS)

    Durst, F.; Zare, M.

    1976-01-01

    Basic theory for laser-Doppler velocity measurements of large reflecting or refracting surfaces is provided. It is shown that the Doppler-signals contain information of the velocity and size of the large bodies, and relationships for transforming velocity and radius of curvature of moving spheres are presented. Preliminary experiments verified the analytical findings and demonstrated the applicability of the method to some two-phase flows

  1. An elementary approach to the gravitational Doppler shift

    International Nuclear Information System (INIS)

    Wörner, C H; Rojas, Roberto

    2017-01-01

    In college physics courses, treatment of the Doppler effect is usually done far from the first introduction to kinematics. This paper aims to apply a graphical treatment to describe the gravitational redshift, by considering the Doppler effect in two accelerated reference frames and exercising the equivalence principle. This approach seems appropriate to discuss with beginner students and could serve to enrich the didactic processes. (paper)

  2. Transcranial Doppler ultrasound and cerebral angiography - alternative or complementary

    International Nuclear Information System (INIS)

    Bockenheimer, S.; Lorey, N.

    1985-01-01

    Transcranial Doppler ultrasound is a noninvasive method of recording the flow velocity of larger intracranial vessels. The impact on diagnosis of cerebravascular occlusive disease is not yet evaluated. We present 15 patients, age range 39-73 years, who suffered from completed stroke. The findings of transcranial Doppler ultrasound and of cerebral angiography are presented. The value of both methods in treatment strategy is discussed. (orig.) [de

  3. Color doppler ultrasound diagonosis in cesarean scar pregnancy

    International Nuclear Information System (INIS)

    Chen Shanshan; Xia Fei; Shen Zongji; Xu Jianyin; Gu Xinxian

    2010-01-01

    Objective: To study the sonographic characteristics of cesarean scar pregnancy(CSP), and the value of color Doppler in the diagnosis of CSP. Methods: Twelve cases of CSP were all confirmed by transabdominal and transvaginal ultrasound. Results: The ultrasonogram of CSP could be divided into gestational sac type and mixed mass type. Conclusion: Color Doppler can give guidance to the early diagnosis, treatment and following-up of CSP because of the sonographic specifity of CSP. (authors)

  4. Prevalência da colonização vaginal e anorretal por estreptococo do grupo B em gestantes do terceiro trimestre Prevalence of vaginal and anorectal colonization by group B streptococcus in pregnant women in the last three months of gestation

    Directory of Open Access Journals (Sweden)

    Cláudio Beraldo

    2004-08-01

    Full Text Available OBJETIVOS: estudar a prevalência da colonização por estreptococo do grupo B em gestantes do terceiro trimestre, atendidas em um hospital regional, e avaliar a associação da colonização com as variáveis maternas demográficas e clínicas. MÉTODOS: no período de 8 de outubro de 2002 a 26 de março de 2003, foi realizado um estudo transversal (de prevalência com 309 gestantes no terceiro trimestre. Amostras de secreção vaginal e anorretal foram coletadas e testadas para identificação presuntiva do estreptococo do grupo B. Foram incluídas as gestantes com gestação maior ou igual a 36 semanas datadas por ultra-sonografia e excluídas as que se recusaram a participar, as em uso de antibioticoterapia e as que haviam sido submetidas a exame ginecológico pelo período mínimo de 24 horas antes da coleta. As gestantes foram caracterizadas por variáveis demográficas (raça, idade, grau de escolaridade, renda familiar e número de gestações e clínicas (idade gestacional, ocorrência de infecção urinária durante a gestação atual, ruptura prematura de membranas e tempo de bolsa rota, febre materna intraparto, corioamnionite, líquido amniótico com mecônio, via de parto utilizada, febre materna pós-parto e endometrite. RESULTADOS: das gestantes, 46 estavam colonizadas pelo estreptococo do grupo B, sendo que 26 (56,5% tiveram a cultura vaginal positiva, 8 (17,4% a cultura anorretal positiva e 12 (26,5% tiveram tanto a cultura vaginal como a retal positivas. Nenhuma das variáveis analisadas neste estudo foi estatisticamente significativa quanto à colonização pelo estreptococo do grupo B. Os resultados obtidos foram submetidos à análise bivariada pelo teste do chi2 e teste exato de Fisher quando apropriado. CONCLUSÃO: a taxa de prevalência da colonização vaginal e anorretal pelo estreptococo do grupo B em gestantes no terceiro trimestre, foi de 14,9%. Não houve associação entre fatores de risco (primigestação, idade

  5. Doppler ultrasound in obstetrics and gynecology. 2. rev. and enl. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Maulik, D. [Winthrop Univ. Hospital, Mineola, NY (United States). Dept. of Obstetrics and Gynecology; Zalud, I. (eds.) [Kapiolani Medical Center for Women and Children, Honolulu, HI (United States)

    2005-07-01

    The second edition of Doppler Ultrasound in Obstetrics and Gynecology has been expanded and comprehensively updated to present the current standards of practice in Doppler ultrasound and the most recent developments in the technology. Doppler Ultrasound in Obstetrics and Gynecology encompasses the full spectrum of clinical applications of Doppler ultrasound for the practicing obstetrician-gynecologist, including the latest advances in 3D and color Doppler and the newest techniques in 4D fetal echocardiography. Written by preeminent experts in the field, the book covers the basic and physical principles of Doppler ultrasound; the use of Doppler for fetal examination, including fetal cerebral circulation; Doppler echocardiography of the fetal heart; and the use of Doppler for postdated pregnancy and in cases of multiple gestation. Chapters on the use of Doppler for gynecologic investigation include ultrasound in ectopic pregnancy, for infertility, for benign disorders and for gynecologic malignancies. (orig.)

  6. Doppler ultrasound in obstetrics and gynecology. 2. rev. and enl. ed.

    International Nuclear Information System (INIS)

    Maulik, D.

    2005-01-01

    The second edition of Doppler Ultrasound in Obstetrics and Gynecology has been expanded and comprehensively updated to present the current standards of practice in Doppler ultrasound and the most recent developments in the technology. Doppler Ultrasound in Obstetrics and Gynecology encompasses the full spectrum of clinical applications of Doppler ultrasound for the practicing obstetrician-gynecologist, including the latest advances in 3D and color Doppler and the newest techniques in 4D fetal echocardiography. Written by preeminent experts in the field, the book covers the basic and physical principles of Doppler ultrasound; the use of Doppler for fetal examination, including fetal cerebral circulation; Doppler echocardiography of the fetal heart; and the use of Doppler for postdated pregnancy and in cases of multiple gestation. Chapters on the use of Doppler for gynecologic investigation include ultrasound in ectopic pregnancy, for infertility, for benign disorders and for gynecologic malignancies. (orig.)

  7. Doppler velocity measurements from large and small arteries of mice

    Science.gov (United States)

    Reddy, Anilkumar K.; Madala, Sridhar; Entman, Mark L.; Michael, Lloyd H.; Taffet, George E.

    2011-01-01

    With the growth of genetic engineering, mice have become increasingly common as models of human diseases, and this has stimulated the development of techniques to assess the murine cardiovascular system. Our group has developed nonimaging and dedicated Doppler techniques for measuring blood velocity in the large and small peripheral arteries of anesthetized mice. We translated technology originally designed for human vessels for use in smaller mouse vessels at higher heart rates by using higher ultrasonic frequencies, smaller transducers, and higher-speed signal processing. With these methods one can measure cardiac filling and ejection velocities, velocity pulse arrival times for determining pulse wave velocity, peripheral blood velocity and vessel wall motion waveforms, jet velocities for the calculation of the pressure drop across stenoses, and left main coronary velocity for the estimation of coronary flow reserve. These noninvasive methods are convenient and easy to apply, but care must be taken in interpreting measurements due to Doppler sample volume size and angle of incidence. Doppler methods have been used to characterize and evaluate numerous cardiovascular phenotypes in mice and have been particularly useful in evaluating the cardiac and vascular remodeling that occur following transverse aortic constriction. Although duplex ultrasonic echo-Doppler instruments are being applied to mice, dedicated Doppler systems are more suitable for some applications. The magnitudes and waveforms of blood velocities from both cardiac and peripheral sites are similar in mice and humans, such that much of what is learned using Doppler technology in mice may be translated back to humans. PMID:21572013

  8. Analysis of Radar Doppler Signature from Human Data

    Directory of Open Access Journals (Sweden)

    M. ANDRIĆ

    2014-04-01

    Full Text Available This paper presents the results of time (autocorrelation and time-frequency (spectrogram analyses of radar signals returned from the moving human targets. When a radar signal falls on the human target which is moving toward or away from the radar, the signals reflected from different parts of his body produce a Doppler shift that is proportional to the velocity of those parts. Moving parts of the body causes the characteristic Doppler signature. The main contribution comes from the torso which causes the central Doppler frequency of target. The motion of arms and legs induces modulation on the returned radar signal and generates sidebands around the central Doppler frequency, referred to as micro-Doppler signatures. Through analyses on experimental data it was demonstrated that the human motion signature extraction is better using spectrogram. While the central Doppler frequency can be determined using the autocorrelation and the spectrogram, the extraction of the fundamental cadence frequency using the autocorrelation is unreliable when the target is in the clutter presence. It was shown that the fundamental cadence frequency increases with increasing dynamic movement of people and simultaneously the possibility of its extraction is proportional to the degree of synchronization movements of persons in the group.

  9. Low-Frequency Gravitational Wave Searches Using Spacecraft Doppler Tracking

    Directory of Open Access Journals (Sweden)

    Armstrong J. W.

    2006-01-01

    Full Text Available This paper discusses spacecraft Doppler tracking, the current-generation detector technology used in the low-frequency (~millihertz gravitational wave band. In the Doppler method the earth and a distant spacecraft act as free test masses with a ground-based precision Doppler tracking system continuously monitoring the earth-spacecraft relative dimensionless velocity $2 Delta v/c = Delta u/ u_0$, where $Delta u$ is the Doppler shift and $ u_0$ is the radio link carrier frequency. A gravitational wave having strain amplitude $h$ incident on the earth-spacecraft system causes perturbations of order $h$ in the time series of $Delta u/ u_0$. Unlike other detectors, the ~1-10 AU earth-spacecraft separation makes the detector large compared with millihertz-band gravitational wavelengths, and thus times-of-flight of signals and radio waves through the apparatus are important. A burst signal, for example, is time-resolved into a characteristic signature: three discrete events in the Doppler time series. I discuss here the principles of operation of this detector (emphasizing transfer functions of gravitational wave signals and the principal noises to the Doppler time series, some data analysis techniques, experiments to date, and illustrations of sensitivity and current detector performance. I conclude with a discussion of how gravitational wave sensitivity can be improved in the low-frequency band.

  10. Calculation of the Doppler broadening function using Fourier analysis;Calculo da funcao de alargamento Doppler utilizando analise de Fourier

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Alessandro da Cruz

    2010-07-01

    An efficient and precise method for calculation of Doppler broadening function is very important to obtain average group microscopic cross sections, self shielding factors, resonance integrals and others reactor physics parameter. In this thesis two different methods for calculation of Doppler broadening function and interference term will be presented. The main method is based on a new integral form for Doppler broadening function {psi}(x,{zeta}) which gives a mathematical interpretation of the approximation proposed by Bethe and Placzek, as the convolution of the Lorentzian function with a Gaussian function. This interpretation besides leading to a new integral form for {psi}(x,{zeta}), enables to obtain a simple analytic solution for the Doppler broadening function. (author)

  11. Pulsed-wave tissue Doppler imaging of the myocardium of cats with induced thyrotoxicosis Doppler tecidual pulsado do miocárdio de gatos com tirotoxicose induzida

    Directory of Open Access Journals (Sweden)

    Daniel Capucho de Oliveira

    2011-06-01

    Full Text Available Left ventricular myocardial motion was quantified using pulsed-wave tissue Doppler imaging (PW-TDI in nine adult cats before and after thyrotoxicosis induction. In order to induce thyrotoxicosis, all cats were given 150µg kg-1 of levothyroxine sodium as a single oral dose each day for 10 weeks. PW-TDI examinations were performed immediately before the induction and by the end of the experimental protocol. An increase in myocardial motion velocity was documented at the interventricular septum level, demonstrated by an elevation in systolic (Sa, and early (Ea and late (Aa diastolic waves (PA velocidade de movimentação miocárdica do ventrículo esquerdo foi quantificada por meio de exames ecocardiográficos com Doppler tecidual pulsado (PW-TDI em nove gatos adultos antes e após indução à tirotoxicose. Para indução da tirotoxicose, todos os gatos receberam doses diárias de 150mg kg-1 de levotiroxina sódica, por via oral, durante 10 semanas. Os exames de PW-TDI foram realizados imediatamente antes da indução e ao final do protocolo experimental. Uma elevação na velocidade de movimentação miocárdica foi documentada ao nível do septo interventricular, demonstrado por um aumento das ondas sistólica (Sa e diastólicas (Ea e Aa; P<0,05. No entanto, nenhuma alteração nos valores de Sa, Ea e Aa foi encontrada ao nível da parede livre do ventrículo esquerdo. A frequência cardíaca aumentou significativamente entre os momentos experimentais, sendo que três animais apresentaram fusão das ondas Aa e Ea ao final do experimento. O protocolo experimental utilizado neste estudo causou alterações na velocidade de movimentação do miocárdio ventricular esquerdo, mas sem causar danos à função diastólica do ventrículo esquerdo.

  12. Transcranial Doppler sonography as diagnostic method

    Directory of Open Access Journals (Sweden)

    Jasminka Đelilović-Vranić

    2002-02-01

    Full Text Available Having in mind the fact that cerebrovascular disease (CVB takes today in medicine, in spite of diagnostic and therapeutic modernisation, the third place of mortality causes in the world (behind cordial and malignant diseases, but in front of depressions, and the second place of invalidity cause (right after trauma as well as the second place of dementia cause (after Alzheimer disease, it urges primary prophylaxis. Developing countries, but before all countries of East and Middle Europe, where is our country, are highly risked areas where CV disease has trend of incidence and total frequency increase. In the neighbouring Croatia today CV disease is at the first place of mortality causes. In the world today 5 million people annually suffer CV disease, in Europe about 700.000, but frequency of suffering on Balkan is about 5 prom. Age of CV disease effecting unfortunately moved towards young age, and today 49% of effected by CV disease are of 46 to 59 years of age. Early detection and treatment of risk factors (before hypertension, smoking, diabetes mellitus, hyperlipidaemia, stress and physical non-activities are the first aspect of CV disease prophylaxis. Together with this aspect of primary prophylaxis is early detection of complications of mentioned risk factors on the walls of blood vessels, before all changing in sense of arteriosclerosis, with consequence of disorder of cerebral haemodynamics. With that objective - verification of circulator and total haemodynamic disorders, there is obvious disclose of non-invasive diagnostic methods, and one of them is Transcranial Doppler Sonography(TCD. TCD is method comfortable for patient, reliable and rather precise, dynamic, and can be repeated several times, without side effects and in comparison with others rather cheap.

  13. Maximisation of the Doppler effect in thermal reactors

    International Nuclear Information System (INIS)

    Bende, E.E.

    1998-03-01

    Increase of the fuel temperature in a nuclear reactor leads, or can lead, to (1) A Doppler broadening of the resonances of the nuclides in the fuel; (2) An expansion of the fuel; and (3) A shift of the Maxwellian part of the spectrum to higher energies. These processes together introduce a certain amount of reactivity, which can be expressed in the so-called fuel temperature reactivity coefficient. The reactivity effect of the third process is very small, because the Maxwell spectrum is to a major extent determined by the moderator temperature. Moreover, the reactivity effect due to an expansion of the fuel is small too, for most thermal systems. When the second and third processes can be neglected, the fuel temperature reactivity effect is fully determined by the Doppler effect. The fuel temperature reactivity coefficient is then called the Doppler coefficient of reactivity. The Doppler broadening of the resonances causes an increase of resonance absorption, due to a decrease of self-shielding. The competition between resonance fission at the one hand and resonance capture at the other hand determines the sign and magnitude of the reactivity induced by an increase of the fuel temperature. In well-designed nuclear reactors the Doppler effect due to resonance capture by fertile nuclides exceeds the Doppler effect due to resonance fission, which implies that an increase of the fuel temperature causes a negative reactivity effect and a correspondingly negative Doppler coefficient. Since the Doppler effect is a prompt effect, occurring simultaneously with the dissipation of kinetic energy of the fission products into temperature, it is very important in the study of rapid power transients. In this report, the Doppler coefficient of reactivity is defined in chapter 2. Chapter 3 discusses the geometry of the unit-cell for which the calculations are performed and describes the fuel types that have been investigated. In chapter 4 the 'Doppler efficiency' is introduced and

  14. Longitudinal study of aortic isthmus Doppler in appropriately grown and small-for-gestational-age fetuses with normal and abnormal umbilical artery Doppler.

    LENUS (Irish Health Repository)

    Kennelly, M M

    2012-04-01

    To establish reference ranges using longitudinal data for aortic isthmus (AoI) Doppler indices in appropriate-for-gestational-age (AGA) fetuses and to document the longitudinal trends in a cohort of small-for-gestational-age (SGA) fetuses with normal umbilical artery Doppler and in fetuses with intrauterine growth restriction (IUGR) and abnormal umbilical artery Doppler.

  15. Apendicitis por Paracoccidioides brasiliensis.

    OpenAIRE

    MUÑOZ URRIBARRI, Ana Beatriz; CHAPARRO DAMMERT, Eduardo; FERRUFINO LLACH, Juan Carlos; VASQUEZ FLORES, Luciola

    2012-01-01

    La paracoccidioidomicosis es la micosis más prevalente en Sudamérica. La forma aguda afecta el sistema fagocítico mononuclear de niños y personas inmunocomprometidas. El compromiso gastrointestinal es frecuente y su patogenia implica diseminación hematógena y linfática. La linfadenomegalia abdominal causa obstrucción intestinal y abdomen agudo. En este artículo damos a conocer el caso de un niño con compromiso gastrointestinal por apendicitis. Este es el primer caso reportado de apendicitis p...

  16. Meningitis por Streptococcus suis

    OpenAIRE

    Geffner Sclarsky, D. E.; Moreno Muñoz, R.; Campillo Alpera, Mª.S.; Pardo Serrano, F.J.; Gómez Gómez, A.; Martínez-Lozano, Mª.D.

    2001-01-01

    La infección humana por Streptococcus suis (S. suis) es una zoonosis, con un riesgo ocupacional conocido y que suele presentarse como meningitis purulenta, que tiene baja mortalidad y frecuentes secuelas de hipoacusia y ataxia. Se han publicado menos de 150 casos humanos desde el informe original de hace 30 años. Hay una reconocida distribución geográfica viviendo la mayoría de los afectados en el norte de Europa y el sudeste Asiático. En España se han comunicado dos pacientes con enfermedad ...

  17. Por mil devaluados pesos

    Directory of Open Access Journals (Sweden)

    Annie Rodríguez Collázos

    2013-03-01

    Full Text Available El estudio de lo popular y lo urbano hasta ahora se ha centrado en el comportamiento y en algunas relaciones de los habitantes con su entorno. “Por mil devaluados pesos. Publicidad popular y urbana”, pretende explorar las formas de publicidad, dispersas en diferentes espacios populares y urbanos en Bogotá, identificando esquemas y formas características de sus propios códigos comunicativos; se centran en un objeto de estudio consistente en las estrategias publicitarias y los códigos comunicativos en los mensajes publicitarios populares en las subculturas de San Victorino, 7 de Agosto y Sanandresito de San José.

  18. Alergia ao leite de vaca: achados do ultrassom com Doppler colorido em neonatos com hematoquezia

    Directory of Open Access Journals (Sweden)

    Matias Epifanio

    2013-12-01

    Full Text Available OBJETIVO: o ultrassom (US tem sido uma importante ferramenta de diagnóstico para identificar várias causas de hemorragia gastrointestinal. Neonatos com alergia ao leite de vaca (ALV podem apresentar hematoquezia, e a confirmação do diagnóstico pode ser difícil. O objetivo deste estudo é descrever achados com ultrassom em escala de cinza e com Doppler colorido em pacientes com ALV. MÉTODOS: estudamos, retrospectivamente, 13 neonatos com ALV. Todos eles apresentaram hematoquezia severa e dor abdominal e foram submetidos a um estudo com US, com o diagnóstico de colite alérgica. O diagnóstico teve como base os achados clínicos, a recuperação após a dieta de exclusão do neonato ou da mãe, no caso de amamentação exclusiva, e o teste de provocação oral positivo. RESULTADOS: a idade média variou de um a seis meses (média = 3,53. Sete dos 13 neonatos (53,8% passaram novamente por ultrassonografia em escala de cinza e com Doppler colorido após a dieta de exclusão. Dentre eles, 12 dos 13 (92,3% mostraram anormalidades no US e no ultrassom com Doppler colorido (USDC no início. Os achados positivos que sugeriram colite foram paredes intestinais espessas e aumento na vascularização, principalmente no cólon descendente e sigmoide. Os resultados da colonoscopia e histopatológicos foram compatíveis com colite alérgica. Após uma mudança na dieta, os 13 neonatos se recuperaram e seus testes de provocação oral foram positivos. CONCLUSÃO: o US com Doppler pode ser muito útil para diagnosticar a colite secundária, como a ALV, e para excluir várias outras doenças abdominais que podem imitar essa doença.

  19. DOPPLER SIGNATURES OF THE ATMOSPHERIC CIRCULATION ON HOT JUPITERS

    International Nuclear Information System (INIS)

    Showman, Adam P.; Lewis, Nikole K.; Fortney, Jonathan J.; Shabram, Megan

    2013-01-01

    The meteorology of hot Jupiters has been characterized primarily with thermal measurements, but recent observations suggest the possibility of directly detecting the winds by observing the Doppler shift of spectral lines seen during transit. Motivated by these observations, we show how Doppler measurements can place powerful constraints on the meteorology. We show that the atmospheric circulation—and Doppler signature—of hot Jupiters splits into two regimes. Under weak stellar insolation, the day-night thermal forcing generates fast zonal jet streams from the interaction of atmospheric waves with the mean flow. In this regime, air along the terminator (as seen during transit) flows toward Earth in some regions and away from Earth in others, leading to a Doppler signature exhibiting superposed blueshifted and redshifted components. Under intense stellar insolation, however, the strong thermal forcing damps these planetary-scale waves, inhibiting their ability to generate jets. Strong frictional drag likewise damps these waves and inhibits jet formation. As a result, this second regime exhibits a circulation dominated by high-altitude, day-to-night airflow, leading to a predominantly blueshifted Doppler signature during transit. We present state-of-the-art circulation models including non-gray radiative transfer to quantify this regime shift and the resulting Doppler signatures; these models suggest that cool planets like GJ 436b lie in the first regime, HD 189733b is transitional, while planets hotter than HD 209458b lie in the second regime. Moreover, we show how the amplitude of the Doppler shifts constrains the strength of frictional drag in the upper atmospheres of hot Jupiters. If due to winds, the ∼2 km s –1 blueshift inferred on HD 209458b may require drag time constants as short as 10 4 -10 6 s, possibly the result of Lorentz-force braking on this planet's hot dayside.

  20. Doppler ultrasound imaging techniques for assessment of synovial inflammation

    Directory of Open Access Journals (Sweden)

    Filippucci E

    2013-09-01

    Full Text Available Emilio Filippucci,1 Fausto Salaffi,1 Marina Carotti,2 Walter Grassi1 1Rheumatology Department, Polytechnic University of the Marche, Ancona, Italy; 2Department of Radiology, Polytechnic University of the Marche, Ancona, Italy Abstract: Ultrasound is an evolving technique, and the rapid progress made in ultrasound technology over the past ten years has dramatically increased its range of applications in rheumatology. One of the most exciting advances is the use of Doppler ultrasound imaging in the assessment of blood flow abnormalities at the synovial tissue level in patients with chronic inflammatory arthritis. This review describes the Doppler techniques available and their main applications in patients with inflammatory arthritis, discusses the evidence supporting their use, and outlines the latest advances in hardware and software. Spectral, color, and power Doppler allow sensitive assessment of vascular abnormalities at the synovial tissue level. Use of contrast agents enhances visualization of the small synovial vessels using color or power Doppler ultrasound and allows for accurate characterization of the rheumatoid pannus. Doppler techniques represent a unique method for assessment of synovial inflammation, showing blood flow characteristics in real time. They are safe, noninvasive, cost-effective, and have high sensitivity in revealing and monitoring synovitis. However, several questions still need to be answered. In the near future, the Doppler techniques described here, together with upcoming hardware and software facilities, will be investigated further and a consensus will be reached on their feasibility and appropriate use in daily rheumatologic practice. Keywords: power and color Doppler techniques, ultrasound, contrast media, synovitis, rheumatoid arthritis

  1. Cross-correlation Doppler global velocimetry (CC-DGV)

    Science.gov (United States)

    Cadel, Daniel R.; Lowe, K. Todd

    2015-08-01

    A flow velocimetry method, cross-correlation Doppler global velocimetry (CC-DGV), is presented as a robust, simplified, and high dynamic range implementation of the Doppler global/planar Doppler velocimetry technique. A sweep of several gigahertz of the vapor absorption spectrum is used for each velocity sample, with signals acquired from both Doppler-shifted scattered light within the flow and a non-Doppler shifted reference beam. Cross-correlation of these signals yields the Doppler shift between them, averaged over the duration of the scan. With presently available equipment, velocities from 0 ms-1 to over 3000 ms-1 can notionally be measured simultaneously, making the technique ideal for high speed flows. The processing routine is shown to be robust against large changes in the vapor pressure of the iodine cell, benefiting performance of the system in facilities where ambient conditions cannot be easily regulated. Validation of the system was performed with measurements of a model wind turbine blade boundary layer made in a 1.83 m by 1.83 m subsonic wind tunnel for which laser Doppler velocimetry (LDV) measurements were acquired alongside the CC-DGV results. CC-DGV uncertainties of ±1.30 ms-1, ±0.64 ms-1, and ±1.11 ms-1 were determined for the orthogonal stream-wise, transverse-horizontal, and transverse-vertical velocity components, and root-mean-square deviations of 2.77 ms-1 and 1.34 ms-1 from the LDV validation results were observed for Reynolds numbers of 1.5 million and 2 million, respectively. Volumetric mean velocity measurements are also presented for a supersonic jet, with velocity uncertainties of ±4.48 ms-1, ±16.93 ms-1, and ±0.50 ms-1 for the orthogonal components, and self-validation done by collapsing the data with a physical scaling.

  2. Re-Normalization Method of Doppler Lidar Signal for Error Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Park, Nakgyu; Baik, Sunghoon; Park, Seungkyu; Kim, Donglyul [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Dukhyeon [Hanbat National Univ., Daejeon (Korea, Republic of)

    2014-05-15

    In this paper, we presented a re-normalization method for the fluctuations of Doppler signals from the various noises mainly due to the frequency locking error for a Doppler lidar system. For the Doppler lidar system, we used an injection-seeded pulsed Nd:YAG laser as the transmitter and an iodine filter as the Doppler frequency discriminator. For the Doppler frequency shift measurement, the transmission ratio using the injection-seeded laser is locked to stabilize the frequency. If the frequency locking system is not perfect, the Doppler signal has some error due to the frequency locking error. The re-normalization process of the Doppler signals was performed to reduce this error using an additional laser beam to an Iodine cell. We confirmed that the renormalized Doppler signal shows the stable experimental data much more than that of the averaged Doppler signal using our calibration method, the reduced standard deviation was 4.838 Χ 10{sup -3}.

  3. Cardiac tissue Doppler imaging in sports medicine.

    Science.gov (United States)

    Krieg, Anne; Scharhag, Jürgen; Kindermann, Wilfried; Urhausen, Axel

    2007-01-01

    The differentiation of training-induced cardiac adaptations from pathological conditions is a key issue in sports cardiology. As morphological features do not allow for a clear delineation of early stages of relevant pathologies, the echocardiographic evaluation of left ventricular function is the technique of first choice in this regard. Tissue Doppler imaging (TDI) is a relatively recent method for the assessment of cardiac function that provides direct, local measurements of myocardial velocities throughout the cardiac cycle. Although it has shown a superior sensitivity in the detection of ventricular dysfunction in clinical and experimental studies, its application in sports medicine is still rare. Besides technical factors, this may be due to a lack in consensus on the characteristics of ventricular function in relevant conditions. For more than two decades there has been an ongoing debate on the existence of a supernormal left ventricular function in athlete's heart. While results from traditional echocardiography are conflicting, TDI studies established an improved diastolic function in endurance-trained athletes with athlete's heart compared with controls.The influence of anabolic steroids on cardiac function also has been investigated by standard echocardiographic techniques with inconsistent results. The only TDI study dealing with this topic demonstrated a significantly impaired diastolic function in bodybuilders with long-term abuse of anabolic steroids compared with strength-trained athletes without abuse of anabolic steroids and controls, respectively.Hypertrophic cardiomyopathy is the most frequent cause of sudden death in young athletes. However, in its early stages, it is difficult to distinguish from athlete's heart. By means of TDI, ventricular dysfunction in hypertrophic cardiomyopathy can be disclosed even before the development of left ventricular hypertrophy. Also, a differentiation of left ventricular hypertrophy due to hypertrophic

  4. Precise Doppler shift compensation in the hipposiderid bat, Hipposideros armiger.

    Science.gov (United States)

    Schoeppler, Diana; Schnitzler, Hans-Ulrich; Denzinger, Annette

    2018-03-15

    Bats of the Rhinolophidae and Hipposideridae families, and Pteronotus parnellii, compensate for Doppler shifts generated by their own flight movement. They adjust their call frequency such that the frequency of echoes coming from ahead fall in a specialized frequency range of the hearing system, the auditory fovea, to evaluate amplitude and frequency modulations in echoes from fluttering prey. Some studies in hipposiderids have suggested a less sophisticated or incomplete Doppler shift compensation. To investigate the precision of Doppler shift compensation in Hipposideros armiger, we recorded the echolocation and flight behaviour of bats flying to a grid, reconstructed the flight path, measured the flight speed, calculated the echo frequency, and compared it with the resting frequency prior to each flight. Within each flight, the average echo frequency was kept constant with a standard deviation of 110 Hz, independent of the flight speed. The resting and reference frequency were coupled with an offset of 80 Hz; however, they varied slightly from flight to flight. The precision of Doppler shift compensation and the offset were similar to that seen in Rhinolophidae and P. parnellii. The described frequency variations may explain why it has been assumed that Doppler shift compensation in hipposiderids is incomplete.

  5. Temporal enhancement of two-dimensional color doppler echocardiography

    Science.gov (United States)

    Terentjev, Alexey B.; Settlemier, Scott H.; Perrin, Douglas P.; del Nido, Pedro J.; Shturts, Igor V.; Vasilyev, Nikolay V.

    2016-03-01

    Two-dimensional color Doppler echocardiography is widely used for assessing blood flow inside the heart and blood vessels. Currently, frame acquisition time for this method varies from tens to hundreds of milliseconds, depending on Doppler sector parameters. This leads to low frame rates of resulting video sequences equal to tens of Hz, which is insufficient for some diagnostic purposes, especially in pediatrics. In this paper, we present a new approach for reconstruction of 2D color Doppler cardiac images, which results in the frame rate being increased to hundreds of Hz. This approach relies on a modified method of frame reordering originally applied to real-time 3D echocardiography. There are no previous publications describing application of this method to 2D Color Doppler data. The approach has been tested on several in-vivo cardiac 2D color Doppler datasets with approximate duration of 30 sec and native frame rate of 15 Hz. The resulting image sequences had equivalent frame rates to 500Hz.

  6. Trans-skull ultrasonic Doppler system aided by fuzzy logic

    Science.gov (United States)

    Hata, Yutaka; Nakamura, Masato; Yagi, Naomi; Ishikawa, Tomomoto

    2012-06-01

    This paper describes a trans-skull ultrasonic Doppler system for measuring the blood flow direction in brain under skull. In this system, we use an ultrasonic array probe with the center frequency of 1.0 MHz. The system determines the fuzzy degree of blood flow by Doppler Effect, thereby it locates blood vessel. This Doppler Effect is examined by the center of gravity shift of the frequency magnitudes. In in-vitro experiment, a cow bone was employed as the skull, and three silicon tubes were done as blood vessels, and bubble in water as blood. We received the ultrasonic waves through a protein, the skull and silicon tubes in order. In the system, fuzzy degrees are determined with respect to the Doppler shift, amplitude of the waves and attenuation of the tissues. The fuzzy degrees of bone and blood direction are calculated by them. The experimental results showed that the system successfully visualized the skull and flow direction, compared with the location and flow direction of the phantom. Thus, it detected the flow direction by Doppler Effect under skull, and automatically extracted the region of skull and blood vessel.

  7. New clutter-rejection algorithm for Doppler ultrasound

    Science.gov (United States)

    Cloutier, Guy; Chen, Danmin; Durand, Louis-Gilles

    2002-04-01

    Several strategies, known as clutter or wall Doppler filtering, were proposed to remove the strong echoes produced by stationary or slow moving tissue structures from the Doppler blood flow signal. In this study, the matching pursuit (MP) method is proposed to remove clutter components. The MP method decomposes the Doppler signal into wavelet atoms that are selected in a decreasing energy order. Thus, the high-energy clutter components are extracted first. In the present study, the pulsatile Doppler signal s(n) was simulated by a sum of random-phase sinusoids. Two types of high-amplitude clutter signals were then superimposed on s(n): a time-varying low frequency component (type 1), covering systole and early diastole, and short transient clutter signals (type 2), distributed within the whole cardiac cycle. The Doppler signals were modeled with the MP method and the most dominant atoms were subtracted until the signal-to-clutter (S/C) ratio reached a maximum. For the type 1 clutter signal, the improvement in the S/C ratio was 19.0 +/- 0.6 dB, and 72.0 +/- 4.5 atoms were required to reach this performance. For the transient type 2 clutter signal, exactly 10 atoms were required and the maximum improvement in S/C ratio was 5.5 +/- 0.5 dB. These results suggest the possibility of using this signal processing approach to implement clutter rejection filters on ultrasound commercial instruments.

  8. Renal Power Doppler Ultrasonographic Evaluation of Children With Acute Pyelonephritis

    Directory of Open Access Journals (Sweden)

    Ali Pahlusi

    2011-10-01

    Full Text Available Urinary tract infections are common in children. The available gold standard method for diagnosis, Tc-99m dimercaptosuccinic acid scan is expensive and exposes patients to considerable amount of radiation. This study was performed to compare and assess the efficacy of Power Doppler Ultrasound versus Tc-99m DMSA scan for diagnosis of acute pyelonephritis. A quasi experimental study was conducted on 34 children with mean age of 2.82.7 years who were hospitalized with their first episode of febrile urinary tract infection. All children were evaluated in the first 3 days of admission by Doppler Ultrasound and Tc-99m DMSA scan. Patients with congenital structural anomalies were excluded. Each kidney was divided into three zones. The comparison between efficacy of Doppler Ultrasound and DMSA scan was carried out based on number of patients and on classified renal units. Based on the number of patients enrolled; the sensitivity, specificity, positive and negative predictive values and accuracy of Doppler Ultrasound were 89%, 53%, 70%, 80% and 74%, respectively but based on the renal units, it was 66%, 81%, 46%, 91% and 79% , respectively. Although Doppler Ultrasound has the potential for identifying acute pyelonephritis in children, but it is still soon to replace DMSA scan.

  9. Spectroscopic Doppler analysis for visible-light optical coherence tomography

    Science.gov (United States)

    Shu, Xiao; Liu, Wenzhong; Duan, Lian; Zhang, Hao F.

    2017-12-01

    Retinal oxygen metabolic rate can be effectively measured by visible-light optical coherence tomography (vis-OCT), which simultaneously quantifies oxygen saturation and blood flow rate in retinal vessels through spectroscopic analysis and Doppler measurement, respectively. Doppler OCT relates phase variation between sequential A-lines to the axial flow velocity of the scattering medium. The detectable phase shift is between -π and π due to its periodicity, which limits the maximum measurable unambiguous velocity without phase unwrapping. Using shorter wavelengths, vis-OCT is more vulnerable to phase ambiguity since flow induced phase variation is linearly related to the center wavenumber of the probing light. We eliminated the need for phase unwrapping using spectroscopic Doppler analysis. We split the whole vis-OCT spectrum into a series of narrow subbands and reconstructed vis-OCT images to extract corresponding Doppler phase shifts in all the subbands. Then, we quantified flow velocity by analyzing subband-dependent phase shift using linear regression. In the phantom experiment, we showed that spectroscopic Doppler analysis extended the measurable absolute phase shift range without conducting phase unwrapping. We also tested this method to quantify retinal blood flow in rodents in vivo.

  10. Response of a Doppler canceling system to plane gravitational waves

    International Nuclear Information System (INIS)

    Caporali, A.

    1982-01-01

    This paper discusses the interaction of long periodic gravitational waves with a three-link microwave system known as the Doppler canceling system. This system, which was developed for gravitational red-shift experiment, uses one-way and two-way Doppler information to construct the beat signal of two reference oscillators moving with respect to each other. The geometric-optics approximation is used to derive the frequency shift produced on a light signal propagating in a gravitational-wave space-time. The signature left on the Doppler-canceled beat by bursts and continuous gravitational waves is analyzed. A comparison is made between the response to gravitational waves of the Doppler canceling system and that of a (NASA) Doppler tracking system which employs two-way, round-trip radio waves. A threefold repetition of the gravitational wave form is found to be a common feature of the response functions of both systems. These two functions otherwise exhibit interesting differences

  11. Acute intrascrotal pathology in childhood: color Doppler study

    International Nuclear Information System (INIS)

    Cinta Sanguesa, C.; Muro, D.; Cortina, H.; Moreno, A.

    1997-01-01

    To asses the utility of color Doppler ultrasound in the study of acute intrascrotal pathology in childhood. Seventy-five boys with evidence of an acute intrascrotal abnormality were studied by means of color Doppler ultrasound. A 7.5 MHz linear transducer was used. The most common findings was inflammatory disease (60%) which was indicated by the presence of hyperemia in color Doppler. Of the nine boys with testicular torsion (12%) two presented extravaginal torsion, with a complete absence of intratesticular vascularization. Intravaginal torsion was observed in seven patients, six of whom presented reduced vascularization in the abnormal testicle with respect to the healthy testicle. There was one false negative in which testicular vascularization was normal but 360 degree centigree torsion was found at surgery. In addition, there were seven cases of hydatid torsion (9.33%), four of idiopathic scrotal swelling (5.3%). two cases of intermittent torsion (2.6%) and one case of Shcolein-Henoch purpura (1.3%). The ultrasound findings were completely nornal in seven boys. Color Doppler is a rapid, noninvasive method for assessing testicular blood flow. The elevated sensitivity and specificity (85.7 and 100%, respectively, in our series) for testicular torsion make Doppler ultrasound a highly reliable method for the study of this disorder. (Author) 18 refs

  12. A study of doppler waveform using pulsatile flow model

    International Nuclear Information System (INIS)

    Chung, Hye Won; Chung, Myung Jin; Park, Jae Hyung; Chung, Jin Wook; Lee, Dong Hyuk; Min, Byoung Goo

    1997-01-01

    Through the construction of a pulsatile flow model using an artificial heart pump and stenosis to demonstrate triphasic Doppler waveform, which simulates in vivo conditions, and to evaluate the relationship between Doppler waveform and vascular compliance. The flow model was constructed using a flowmeter, rubber tube, glass tube with stenosis, and artificial heart pump. Doppler study was carried out at the prestenotic, poststenotic, and distal segments;compliance was changed by changing the length of the rubber tube. With increasing proximal compliance, Doppler waveforms show decreasing peak velocity of the first phase and slightly delayed acceleration time, but the waveform itself did not change significantly. Distal compliance influenced the second phase, and was important for the formation of pulsus tardus and parvus, which without poststenotic vascular compliance, did not develop. The peak velocity of the first phase was inversely proportional to proximal compliance, and those of the second and third phases were directly proportional to distal compliance. After constructing this pulsatile flow model, we were able to explain the relationship between vascular compliance and Doppler waveform, and also better understand the formation of pulsus tardus and parvus

  13. Ovários policísticos: critérios hemodinâmicos

    OpenAIRE

    Ávila,Márcio Augusto Pinto de; Murta,Carlos Geraldo Viana

    2001-01-01

    O advento da ultra-sonografia endovaginal de alta resolução abriu novas áreas de pesquisa nos ovários policísticos. O conhecimento da hemodinâmica ovariana é fundamental para o entendimento do comportamento fisiopatológico dos ovários policísticos. Os autores tecem considerações sobre a possibilidade da utilização do Doppler colorido na melhor definição dos ovários policísticos. Os dados sugerem que o aumento da vascularidade e a diminuição da resistência dos vasos do estroma ovariano, assim ...

  14. Sepsis por shigella flexneri

    Directory of Open Access Journals (Sweden)

    César Cabrera C

    2005-04-01

    Full Text Available Se presenta un caso raro de sepsis por Shigella flexneri en una paciente de 45 años de edad quien estando hospitalizada para el estudio de un tumor cerebral, requirió el uso de manitol y dosis altas de corticoides; luego de ello presenta deposiciones líquidas con moco y sangre, desarrolla síndrome de respuesta inflamatoria sistémica, luego se aísla Shigella flexneri en el hemocultivo; recibió tratamiento antibiótico con ciprofloxacina. Se describen las características del caso y se comenta de acuerdo con la revisión de literatura.

  15. Portable exhausters POR-004 SKID B, POR-005 SKID C, POR-006 SKID D storage plan

    International Nuclear Information System (INIS)

    Nelson, O.D.; Keller, G.M.

    1997-01-01

    This document provides a storage plan for portable exhausters POR-004 SKID B, POR-005 SKID C, AND POR-006 SKID D. The exhausters will be stored until they are needed by the TWRS (Tank Waste Remediation Systems) Saltwell Pumping Program. The storage plan provides criteria for portable exhauster storage, periodic inspections during storage, and retrieval from storage

  16. The Doppler paradigm and the APEX-EPOS-ORANGE quandary

    International Nuclear Information System (INIS)

    Griffin, J.J.

    1995-01-01

    The experimental detection of the sharp lines of the (e + e - ) Puzzle is viewed as a struggle against Doppler broadening. Gedanken experiments which are realistic in zeroth order of detail are analyzed to show that the ORANGE and EPOS/I geometries select narrower slices of a Doppler broadened line than spherically inclusive (APEX and EPOS/II -like) apparati. Roughly speaking, the latter require event-by-event Doppler reconstruction simply to regain an even footing with the former. This suggests that APEX' or EPOS/II's coincident pair distributions must be statistically superior to those of EPOS/I or ORANGE in order to support a comparable inference about sharp structure. Under such circumstances, independent alternative data is invaluable. Therefore, a corroboration of Sakai's 330.1 keV ( + or e - bombardments of U and Th targets could prove crucial

  17. Moving Target Detection With Compact Laser Doppler Radar

    Science.gov (United States)

    Sepp, G.; Breining, A.; Eisfeld, W.; Knopp, R.; Lill, E.; Wagner, D.

    1989-12-01

    This paper describes an experimental integrated optronic system for detection and tracking of moving objects. The system is based on a CO2 waveguide laser Doppler ra-dar with homodyne receiver and galvanometer mirror beam scanner. A "hot spot" seeker consisting of a thermal imager with image processor transmits the coordinates of IR-emitting, i.e. potentially powered, objects to the laser radar scanner. The scanner addresses these "hot" locations operating in a large field-of-view (FOV) random ac-cess mode. Hot spots exhibiting a Doppler shifted laser signal are indicated in the thermal image by velocity-to-colour encoded markers. After switching to a small FOV scanning mode, the laser Doppler radar is used to track fast moving objects. Labora-tory and field experiments with moving objects including rotating discs, automobiles and missiles are described.

  18. [Doppler echocardiography of tricuspid insufficiency. Methods of quantification].

    Science.gov (United States)

    Loubeyre, C; Tribouilloy, C; Adam, M C; Mirode, A; Trojette, F; Lesbre, J P

    1994-01-01

    Evaluation of tricuspid incompetence has benefitted considerably from the development of Doppler ultrasound. In addition to direct analysis of the valves, which provides information about the mechanism involved, this method is able to provide an accurate evaluation, mainly through use of the Doppler mode. In addition to new criteria being evaluated (mainly the convergence zone of the regurgitant jet), some indices are recognised as good quantitative parameters: extension of the regurgitant jet into the right atrium, anterograde tricuspid flow, laminar nature of the regurgitant flow, analysis of the flow in the supra-hepatic veins, this is only semi-quantitative, since the calculation of the regurgitation fraction from the pulsed Doppler does not seem to be reliable; This accurate semi-quantitative evaluation is made possible by careful and consistent use of all the criteria available. The authors set out to discuss the value of the various evaluation criteria mentioned in the literature and try to define a practical approach.

  19. 3D atom microscopy in the presence of Doppler shift

    Science.gov (United States)

    Rahmatullah; Chuang, You-Lin; Lee, Ray-Kuang; Qamar, Sajid

    2018-03-01

    The interaction of hot atoms with laser fields produces a Doppler shift, which can severely affect the precise spatial measurement of an atom. We suggest an experimentally realizable scheme to address this issue in the three-dimensional position measurement of a single atom in vapors of rubidium atoms. A three-level Λ-type atom-field configuration is considered where a moving atom interacts with three orthogonal standing-wave laser fields and spatial information of the atom in 3D space is obtained via an upper-level population using a weak probe laser field. The atom moves with velocity v along the probe laser field, and due to the Doppler broadening the precision of the spatial information deteriorates significantly. It is found that via a microwave field, precision in the position measurement of a single hot rubidium atom can be attained, overcoming the limitation posed by the Doppler shift.

  20. Determination of intestinal viability by Doppler ultrasonography in venous infarction.

    Science.gov (United States)

    Cooperman, M; Martin, E W; Carey, L C

    1980-01-01

    The accuracy of Doppler ultrasound in predicting the viability of ischemic intestine secondary to venous obstruction was assessed. Twenty loops of ischemic intestine were created in dogs by temporarily obstructing venous return from the bowel. Doppler arterial flow signals within the intestine quickly disappeared following venous occlusion. In ten segments, arterial signals promptly returned following release of venous occlusion. Nine of these ten segments were viable at reoperation 24 hours later. In ten segments, no arterial signals could be detected following release of venous occlusion, and only one segment proved to be viable. Doppler ultrasound findings were far more accurate in distinguishing between viable and nonviable intestine thatn were clinical guides to intestinal viability. PMID:7352777

  1. Modeling and processing of laser Doppler reactive hyperaemia signals

    Science.gov (United States)

    Humeau, Anne; Saumet, Jean-Louis; L'Huiller, Jean-Pierre

    2003-07-01

    Laser Doppler flowmetry is a non-invasive method used in the medical domain to monitor the microvascular blood cell perfusion through tissue. Most commercial laser Doppler flowmeters use an algorithm calculating the first moment of the power spectral density to give the perfusion value. Many clinical applications measure the perfusion after a vascular provocation such as a vascular occlusion. The response obtained is then called reactive hyperaemia. Target pathologies include diabetes, hypertension and peripheral arterial occlusive diseases. In order to have a deeper knowledge on reactive hyperaemia acquired by the laser Doppler technique, the present work first proposes two models (one analytical and one numerical) of the observed phenomenon. Then, a study on the multiple scattering between photons and red blood cells occurring during reactive hyperaemia is carried out. Finally, a signal processing that improves the diagnosis of peripheral arterial occlusive diseases is presented.

  2. Three-dimensional laser cooling at the Doppler limit

    Science.gov (United States)

    Chang, R.; Hoendervanger, A. L.; Bouton, Q.; Fang, Y.; Klafka, T.; Audo, K.; Aspect, A.; Westbrook, C. I.; Clément, D.

    2014-12-01

    Many predictions of Doppler-cooling theory of two-level atoms have never been verified in a three-dimensional geometry, including the celebrated minimum achievable temperature ℏ Γ /2 kB , where Γ is the transition linewidth. Here we show that, despite their degenerate level structure, we can use helium-4 atoms to achieve a situation in which these predictions can be verified. We make measurements of atomic temperatures, magneto-optical trap sizes, and the sensitivity of optical molasses to a power imbalance in the laser beams, finding excellent agreement with Doppler theory. We show that the special properties of helium, particularly its small mass and narrow transition linewidth, prevent effective sub-Doppler cooling with red-detuned optical molasses. This discussion can be generalized to identify when a given species is likely to be subject to the same limitation.

  3. Lorentz invariance and the rotor Doppler shift experiments

    International Nuclear Information System (INIS)

    Rodrigues Junior, W.A.; Tiomno, J.

    1984-01-01

    It is shown that 'Rotor Doppler shift Experiments' provide a way to distinguish Einstein's Special Relativity (SR) from Lorentz's Aether Theory (LAT). Misconceptions in previous papers involving the Doppler shift experiments are examined. The theoretical and experimental data available on rotor Doppler shift experiments are analysed. Two models of SR violating theories are used to predict the output of a recently proposed experiment by Torr and Kolen. The first one corresponds to (strict) LAT and the other to an extended form of LAT Contrary to the first, the second theory leads to results in agreement with the preliminary experimental data of Torr et al indicating a breakdown both of SR and strict LAT. (Author) [pt

  4. Lorentz invariance and the rotor Doppler shift experiments

    International Nuclear Information System (INIS)

    Rodrigues Junior, W.A.; Tiomno, J.

    1984-01-01

    It is shown that 'Rotor Doppler shift Experiments' provide a way to distinguish Einstein's Special Relativity (SR) from Lorentz's Aether Theory (LAT). Misconceptions in previous papers involving the Doppler shift experiments are examined. The theoretical and experimental data available on rotor Doppler shift experiments are analysed. Two models of SR violating theories are used to predict the output of a recently proposed experiment by Torr and Kolen. The first one corresponds to (strict) LAT and the other to an extended form of LAT. Contrary to the first, the second theory leads to results in agreement with the preliminary experimental data of Torr et al indicating a breakdown both of SR and strict LAT. (Author) [pt

  5. Void effects on BWR Doppler and void reactivity feedback

    International Nuclear Information System (INIS)

    Hsiang-Shou Cheng; Diamond, D.J.

    1978-01-01

    The significance of steam voids and control rods on the Doppler feedback in a gadolinia shimmed BWR is demonstrated. The importance of bypass voids when determining void feedback is also shown. Calculations were done using a point model, i.e., feedback was expressed in terms of reactivity coefficients which were determined for individual four-bundle configurations and then appropriately combined to yield reactor results. For overpower transients the inclusion of the void effect of control rods is to reduce Doppler feedback. For overpressurization transients the inclusion of the effect of bypass void wil increase the reactivity due to void collapse. (author)

  6. Optical Doppler tomography based on a field programmable gate array

    DEFF Research Database (Denmark)

    Larsen, Henning Engelbrecht; Nilsson, Ronnie Thorup; Thrane, Lars

    2008-01-01

    We report the design of and results obtained by using a field programmable gate array (FPGA) to digitally process optical Doppler tomography signals. The processor fits into the analog signal path in an existing optical coherence tomography setup. We demonstrate both Doppler frequency and envelope...... extraction using the Hilbert transform, all in a single FPGA. An FPGA implementation has certain advantages over general purpose digital signal processor (DSP) due to the fact that the processing elements operate in parallel as opposed to the DSP. which is primarily a sequential processor....

  7. Analysis of multiple scattering effects in optical Doppler tomography

    DEFF Research Database (Denmark)

    Yura, H.T.; Thrane, L.; Andersen, Peter E.

    2005-01-01

    Optical Doppler tomography (ODT) combines Doppler velocimetry and optical coherence tomography (OCT) to obtain high-resolution cross-sectional imaging of particle flow velocity in scattering media such as the human retina and skin. Here, we present the results of a theoretical analysis of ODT where...... multiple scattering effects are included. The purpose of this analysis is to determine how multiple scattering affects the estimation of the depth-resolved localized flow velocity. Depth-resolved velocity estimates are obtained directly from the corresponding mean or standard deviation of the observed...

  8. Prenatal color Doppler ultrasonographic diagnosis of fetal tetralogy of Fallot

    International Nuclear Information System (INIS)

    Tan Buqiao

    2009-01-01

    Objective: To investigate the sonographic findings of tetralogy of Fallot in fetuses. Methods: The data of color Doppler ultrasonography and follow-up results of 5 fetal tetralogy of Fallot were analyzed retrospectively, and their abnormal ultrasound imaging characteristic were summarized. Results: Two cases were proved tetralogy of Fallot by autopsy, and three cases were confirmed to be tetralogy of Fallot by echocardiography after birth. The image features were the main aorta situated above the ventricular septal defect, pulmonary stenosis, no obvious thickening of the right wall. Conclusion: Fetal tetralogy of Fallot have characteristic ultrasound images, prenatal color Doppler ultrasonographic can diagnoses fetal tetralogy of Fallot correctly and has important clinical value. (authors)

  9. The Dependence of the Resonance Integral on the Doppler Effect

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, J

    1960-12-15

    The Doppler sensitive contributions to the resonance integral for metal and oxide cylinders have been calculated using tables compiled by Adler, Hinman and Nordheim. The temperatures 20, 200, 350, 500 and 650 deg C have been investigated for the pure metal and 20, 300, 600, 900 and 1200 deg C for the oxide. Contributions from the separate resonances in the resolved region and for certain energies in the unresolved region are accounted for in detail. Integration over adequate statistical distributions has been carried out for the resonance parameters in the unresolved region. The increase in the resonance integral at elevated temperatures due to the Doppler effect is given separately in tables and diagrams.

  10. Spectral fine structure effects on material and doppler reactivity worth

    International Nuclear Information System (INIS)

    Greenspan, E.; Karni, Y.

    1975-01-01

    New formulations concerning the fine structure effects on the reactivity worth of resonances are developed and conclusions are derived following the extension to more general types of perturbations which include: the removal of resonance material at finite temperatures and the temperature variation of part of the resonance material. It is concluded that the flux method can overpredict the reactivity worth of resonance materials more than anticipated. Calculations on the Doppler worth were carried out; the results can be useful for asessing the contribution of the fine structure effects to the large discrepancy that exists between the calculated and measured small sample Doppler worths. (B.G.)

  11. Method and apparatus for Doppler frequency modulation of radiation

    Science.gov (United States)

    Margolis, J. S.; Mccleese, D. J.; Shumate, M. S.; Seaman, C. H. (Inventor)

    1980-01-01

    A method and apparatus are described for frequency modulating radiation, such as from a laser, for optoacoustic detectors, interferometers, heterodyne spectrometers, and similar devices. Two oppositely reciprocating cats-eye retroreflectors are used to Doppler modulate the radiation. By reciprocally moving both retroreflectors, the center of mass is maintained constant to permit smooth operation at many Hertz. By slightly offsetting the axis of one retroreflector relative to the other, multiple passes of a light beam may be achieved for greater Doppler shifts with the same reciprocating motion of the retroreflectors.

  12. Calculation results and experimental testing of doppler feedback coefficients

    International Nuclear Information System (INIS)

    Yang Shunhai

    1989-01-01

    The Doppler feedback coefficients are calculated by the interpolation and group collapsing method from multigroup self-shielding factors and infinite dilution cross sections rather than effective resonance integrals by using resonance data base. Since many updated sets of multigroup data are in existence to be selected, the calculation process can be simplified. The heterogeneous effects are taken into account by equivalence relation. The computer code of Doppler feedback coefficients is created on computer CYBER-825 and PDP-11. The results calculated are in good agreement with the experiments

  13. Imaging doppler lidar for wind turbine wake profiling

    Science.gov (United States)

    Bossert, David J.

    2015-11-19

    An imaging Doppler lidar (IDL) enables the measurement of the velocity distribution of a large volume, in parallel, and at high spatial resolution in the wake of a wind turbine. Because the IDL is non-scanning, it can be orders of magnitude faster than conventional coherent lidar approaches. Scattering can be obtained from naturally occurring aerosol particles. Furthermore, the wind velocity can be measured directly from Doppler shifts of the laser light, so the measurement can be accomplished at large standoff and at wide fields-of-view.

  14. Doppler-broadening of positron annihilation in a biological environment

    International Nuclear Information System (INIS)

    Torrisi, L.; La Mela, C.; Catania, Univ.

    1997-01-01

    The aim of this study was to investigate the Doppler effect of the 511 keV γ peak from positron annihilation in biological matter: The broadening of the annihilation peak is due to positron annihilation with electrons that have high momentum. In aqueous solutions annihilation depends on the temperature and it is linked positronium formation. Measurements in vivo, on human brain, were taken during the diagnosis of positron emission tomography (PET) on healthy patients by injecting them with the beta emitter of short lifetime 18F . The Doppler-broadening in biological tissues rich in water content decreased significantly compared to biological solutions and water

  15. Control Multivariable por Desacoplo

    Directory of Open Access Journals (Sweden)

    Fernando Morilla

    2013-01-01

    Full Text Available Resumen: La interacción entre variables es una característica inherente de los procesos multivariables, que dificulta su operación y el diseño de sus sistemas de control. Bajo el paradigma de Control por desacoplo se agrupan un conjunto de metodologías, que tradicionalmente han estado orientadas a eliminar o reducir la interacción, y que recientemente algunos investigadores han reorientado con objetivos de solucionar un problema tan complejo como es el control multivariable. Parte del material descrito en este artículo es bien conocido en el campo del control de procesos, pero la mayor parte de él son resultados de varios años de investigación de los autores en los que han primado la generalización del problema, la búsqueda de soluciones de fácil implementación y la combinación de bloques elementales de control PID. Esta conjunción de intereses provoca que no siempre se pueda conseguir un desacoplo perfecto, pero que sí se pueda conseguir una considerable reducción de la interacción en el nivel básico de la pirámide de control, en beneficio de otros sistemas de control que ocupan niveles jerárquicos superiores. El artículo resume todos los aspectos básicos del Control por desacoplo y su aplicación a dos procesos representativos: una planta experimental de cuatro tanques acoplados y un modelo 4×4 de un sistema experimental de calefacción, ventilación y aire acondicionado. Abstract: The interaction between variables is inherent in multivariable processes and this fact may complicate their operation and control system design. Under the paradigm of decoupling control, several methodologies that traditionally have been addressed to cancel or reduce the interactions are gathered. Recently, this approach has been reoriented by several researchers with the aim to solve such a complex problem as the multivariable control. Parts of the material in this work are well known in the process control field; however, most of them are

  16. Correlation between Doppler flow patterns in growth-restricted fetuses and neonatal circulation

    NARCIS (Netherlands)

    Tanis, J. C.; Boelen, M. R.; Schmitz, D. M.; Casarella, L.; van der Laan, M. E.; Bos, A. F.; Bilardo, C. M.

    Objectives To investigate whether prenatal Doppler parameters in growth-restricted fetuses are correlated with neonatal circulatory changes. Methods In 43 cases of suspected fetal growth restriction (FGR), serial Doppler measurements of umbilical artery (UA) and middle cerebral artery (MCA)

  17. Acoustic doppler methods for remote measurements of ocean flows - a review

    Digital Repository Service at National Institute of Oceanography (India)

    Joseph, A.

    The evolution of acoustic doppler methods for remote measurements of ocean flows has been briefly reviewed in historical perspective. Both Eulerian and profiling methods have been discussed. Although the first acoustic Doppler current meter has been...

  18. Color Doppler Ultrasonographic Findings of Vascular Leiomyoma: Pathologic Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Ji Young; Koh, Sung Hye; Min, Soo Kee; Choi, A Lam; Jang, Kyung Mi; Lee, Yul; Lee, Kwan Seop; Lee, Hyun; Sohn, Jeong Hee [Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Kim, Sam Soo [Kangwon National University College of Medicine, Chuncheon (Korea, Republic of)

    2009-12-15

    To evaluate the distribution of color flow signals on color Doppler ultrasonography of vascular leiomyomas and to correlate them with pathologic findings. We retrospectively analyzed color Doppler ultrasonographic images and pathologic slides of six vascular leiomyomas. We classified the patterns of distribution of color flow signals into localized compact cluster types and non-cluster types, and the pathologic findings into three subtypes: solid, venous and cavernous. All cases showed well-defined homogenous hypoechoic subcutaneous masses on gray-scale ultrasonography. Three cases showed localized compact cluster types on color Doppler ultrasonography, one in each subtype (solid, venous and cavernous). For the three non-cluster types, again there was on in each subtype. In addition, on pathologic analysis the zone of the localized compact cluster of color flow signals coincided with a cluster of larger, vascular caliber masses. Localized compact clusters of color flow signals on color Doppler ultrasonography were seen in 50% of our cases and correlated with a cluster of larger vascular caliber in the mass. But the pattern of distribution of color flows didn't show a correlation with pathologic type

  19. Color Doppler Ultrasonographic Findings of Vascular Leiomyoma: Pathologic Correlation

    International Nuclear Information System (INIS)

    Ko, Ji Young; Koh, Sung Hye; Min, Soo Kee; Choi, A Lam; Jang, Kyung Mi; Lee, Yul; Lee, Kwan Seop; Lee, Hyun; Sohn, Jeong Hee; Kim, Sam Soo

    2009-01-01

    To evaluate the distribution of color flow signals on color Doppler ultrasonography of vascular leiomyomas and to correlate them with pathologic findings. We retrospectively analyzed color Doppler ultrasonographic images and pathologic slides of six vascular leiomyomas. We classified the patterns of distribution of color flow signals into localized compact cluster types and non-cluster types, and the pathologic findings into three subtypes: solid, venous and cavernous. All cases showed well-defined homogenous hypoechoic subcutaneous masses on gray-scale ultrasonography. Three cases showed localized compact cluster types on color Doppler ultrasonography, one in each subtype (solid, venous and cavernous). For the three non-cluster types, again there was on in each subtype. In addition, on pathologic analysis the zone of the localized compact cluster of color flow signals coincided with a cluster of larger, vascular caliber masses. Localized compact clusters of color flow signals on color Doppler ultrasonography were seen in 50% of our cases and correlated with a cluster of larger vascular caliber in the mass. But the pattern of distribution of color flows didn't show a correlation with pathologic type

  20. Transcranial Doppler for detection of cerebral ischaemia during carotid endarterectomy

    DEFF Research Database (Denmark)

    Jørgensen, L G; Schroeder, T V

    1992-01-01

    We evaluated transcranial Doppler sonography (TCD) for the detection of cerebral ischaemia during carotid endarterectomy in 30 male and 14 female patients with ipsilateral focal cerebro-vascular symptoms. Surgery was performed during halothane-nitrous oxide anaesthesia with moderate hypocapnia...

  1. Color Doppler Echocardiographic Assessment of Valvular Regurgitation in Normal Infants

    Directory of Open Access Journals (Sweden)

    Shu-Ting Lee

    2010-01-01

    Conclusion: The prevalence of inaudible valvular regurgitation is high in infants with structurally normal hearts. Multiple-valve involvement with regurgitation is not uncommon. Mild severity and low velocity on color Doppler, and the structural information provided by 2D imaging strongly suggest that these regurgitant flows are physiologically normal in infancy.

  2. A simplified study of trans-mitral Doppler patterns

    Directory of Open Access Journals (Sweden)

    Thomas George

    2008-11-01

    Full Text Available Abstract Background Trans-mitral Doppler produces complex patterns with a great deal of variability. There are several confusing numerical measures and indices to study these patterns. However trans-mitral Doppler produces readymade data visualization by pattern generation which could be interpreted by pattern analysis. By following a systematic approach we could create an order and use this tool to study cardiac function. Presentation of the hypothesis In this new approach we eliminate the variables and apply pattern recognition as the main criterion of study. Proper terminologies are also devised to avoid confusion. In this way we can get some meaningful information. Testing the hypothesis Trans-mitral Doppler should be seen as patterns rather than the amplitude. The hypothesis can be proven by logical deduction, extrapolation and elimination of variables. Trans-mitral flow is also analyzed vis-à-vis the Starling's Law applied to the left atrium. Implications of the hypothesis Trans-mitral Doppler patterns are not just useful for evaluating diastolic function. They are also useful to evaluate systolic function. By following this schema we could get useful diagnostic information and therapeutic options using simple pattern recognition with minimal measurements. This simplified but practical approach will be useful in day to day clinical practice and help in understanding cardiac function better. This will also standardize research and improve communication.

  3. Language Lateralization in Children Using Functional Transcranial Doppler Sonography

    Science.gov (United States)

    Haag, Anja; Moeller, Nicola; Knake, Susanne; Hermsen, Anke; Oertel, Wolfgang H.; Rosenow, Felix; Hamer, Hajo M.

    2010-01-01

    Aim: Language lateralization with functional transcranial Doppler sonography (fTCD) and lexical word generation has been shown to have high concordance with the Wada test and functional magnetic resonance imaging in adults. We evaluated a nonlexical paradigm to determine language dominance in children. Method: In 23 right-handed children (12…

  4. Ultrasonography and color Doppler in juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Laurell, Louise; Court-Payen, Michel; Nielsen, Susan

    2012-01-01

    The wrist region is one of the most complex joints of the human body. It is prone to deformity and functional impairment in juvenile idiopathic arthritis (JIA), and is difficult to examine clinically. The aim of this study was to evaluate the role of ultrasonography (US) with Doppler in diagnosis...

  5. Ultrasonography and color Doppler in juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Laurell, Louise; Court-Payen, Michel; Nielsen, Susan

    2011-01-01

    hypertrophy, effusion) and by color Doppler (synovial hyperemia) before and 4 weeks after US-guided steroid injection. Results US detected 121 compartments with active disease (joints, tendon sheaths and 1 ganglion cyst). Multiple compartments were involved in 80% of the ankle regions. The talo-crural joint...

  6. Renal Doppler Indices in Children with Nephrotic Syndrome ...

    African Journals Online (AJOL)

    Summary: The resistive and pulsatility indices are known tools for assessing renal function in kidney diseases, especially in proteinuric conditions like Paediatric Nephrotic syndrome (NS) which is a glomerular disease. However, there is a limited knowledge in the use of Doppler Resistive and pulsatility indices in the ...

  7. Development of Rayleigh Doppler lidar for measuring middle atmosphere winds

    Science.gov (United States)

    Raghunath, K.; Patra, A. K.; Narayana Rao, D.

    Interpretation of most of the middle and upper atmospheric dynamical and chemical data relies on the climatological description of the wind field Rayleigh Doppler lidar is one instrument which monitors wind profiles continuously though continuity is limited to clear meteorological conditions in the middle atmosphere A Doppler wind lidar operating in incoherent mode gives excellent wind and temperature information at these altitudes with necessary spectral sensitivity It observes atmospheric winds by measuring the spectral shift of the scattered light due to the motions of atmospheric molecules with background winds and temperature by spectral broadening The presentation is about the design and development of Incoherent Doppler lidar to obtain wind information in the height regions of 30-65 km The paper analyses and describes various types of techniques that can be adopted viz Edge technique and Fringe Imaging technique The paper brings out the scientific objectives configuration simulations error sources and technical challenges involved in the development of Rayleigh Doppler lidar The presentation also gives a novel technique for calibrating the lidar

  8. Flow Profile Study using miniature Laser-Doppler velocimetry

    NARCIS (Netherlands)

    Booij, W.E.; Booij, W.E.; de Jongh, A.; de Mul, F.F.M.

    1995-01-01

    We present a physics experiment, in which laser - Doppler velocimetry is used to make first - year university physics students realize that the idealized solutions offered by standard text books seldom are applicable without corrections, which often are numerical. This is demonstrated by carefully

  9. Estimation of amputation level with a laser Doppler flowmeter

    DEFF Research Database (Denmark)

    Gebuhr, Peter Henrik; Jørgensen, J P; Vollmer-Larsen, B

    1989-01-01

    Leg amputation levels were decided in 24 patients suffering from atherosclerosis, using the conventional techniques of segmental blood pressure and radioisotope skin clearance. The skin microcirculation was measured and recorded before operation with a laser doppler flowmeter. A high correlation...... was found between the successful amputation levels and the maximal blood perfusion of the skin measured in this way....

  10. Anomaly Detection In Additively Manufactured Parts Using Laser Doppler Vibrometery

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, Carlos A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-09-29

    Additively manufactured parts are susceptible to non-uniform structure caused by the unique manufacturing process. This can lead to structural weakness or catastrophic failure. Using laser Doppler vibrometry and frequency response analysis, non-contact detection of anomalies in additively manufactured parts may be possible. Preliminary tests show promise for small scale detection, but more future work is necessary.

  11. Augmented Reality Based Doppler Lidar Data Visualization: Promises and Challenges

    Directory of Open Access Journals (Sweden)

    Cherukuru N. W.

    2016-01-01

    As a proof of concept, we used the lidar data from a recent field campaign and developed a smartphone application to view the lidar scan in augmented reality. In this paper, we give a brief methodology of this feasibility study, present the challenges and promises of using AR technology in conjunction with Doppler wind lidars.

  12. Three-dimensional colour Doppler of ductus venosus agenesis in ...

    African Journals Online (AJOL)

    was bilateral pleural effusion with generalised subcutaneous oedema suggestive of hydrops fetalis (Fig. 1B). Colour Doppler sonography revealed the umbilical vein draining into the portal sinus with non-visualisation of the DV, which would connect the portal sinus with the inferior vena cava (IVC) (Figs 1C and 1D). Hence ...

  13. Measurement of cylindrical particles with phase Doppler anemometry.

    Science.gov (United States)

    Mignon, H; Gréhan, G; Gouesbet, G; Xu, T H; Tropea, C

    1996-09-01

    Light scattering from cylindrical particles has been described with geometric optics. The feasibility of determining the particle diameter with a planar phase Doppler anemometer has been examined by simulations and experiments. In particular, the influence of particle orientation on measurability and measurement accuracy has been investigated. Some recommendations for realizing a practical-measurement instrument have been presented.

  14. Color M-mode and pulsed wave tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Møller, J E; Søndergaard, E; Poulsen, S H

    2001-01-01

    To assess the association between color M-mode flow propagation velocity and the early diastolic mitral annular velocity (E(m)) obtained with tissue Doppler echocardiography and to assess the prognostic implications of the indexes, echocardiography was performed on days 1 and 5, and 1 and 3 month...

  15. Role of color Doppler ultrasound in the diagnosis of nonpalpable ...

    African Journals Online (AJOL)

    excluded from the study. Color Doppler was performed in all cases, followed by laparoscopy. Further, findings on laparoscopy were compared with those of CDUS. A 95% confidence interval for the sensitivity of CDUS was estimated considering a positive result on CDUS as the binomial variable. Results. Out of 25 patients, ...

  16. Christian Andreas Doppler--the man and his legacy.

    Science.gov (United States)

    Coman, I M

    2005-01-01

    Reminding the life and legacy of the Austrian Scientist who discovered the famous 'Doppler Effect'. C.A. Doppler was born the 29th of November 1803 in Salzburg. After studies in Linz and Vienna, he graduated in mathematics, became assistant at the University and later worked as a professor in Prague. Back to Vienna, he was appointed as professor at the Polytechnic School and --in 1850--as first director of the new Institute of Physics. C.A. Doppler did publish on magnetism, electricity, optics, and astronomy. He remains in the history of science due to the discovery presented (May 25, 1842) at the Royal Bohemian Society of Science entitled "On the colored light of the double stars and certain other stars of the heavens"; the paper described (applied to light) the shift of frequency which bears nowadays his name. The theory was later experimentally proven and--extended for any electromagnetic and acoustic waves--got myriads if applications in astronomy, physics, aviation, meteorology, and health science. Satomura in Japan (1955) published it's first ultrasound vascular application--with successive achievements in the next decades. Doppler ultrasonagraphy became the main noninvasive instrument for functional assesment of heart and vessels.

  17. 3D power Doppler ultrasound in early diagnosis of preeclampsia.

    Science.gov (United States)

    Neto, R Moreira; Ramos, J G L

    2016-01-01

    Preeclampsia is a known cause of maternal, fetal and neonatal morbidity and mortality. Thus, evaluation of the predicting value of comparing 3D power Doppler indices (3DPD) of uteroplacental circulation (UPC) in the first and second trimester in patients who developed preeclampsia (PE) and those who did not and testing the hypothesis that the parameters of vascularization and placenta flow intensity, as determined by three-dimensional ultrasound (3D), are different in normal pregnancies compared with preeclampsia, could be a suitable screening method. A prospective observational study using 3D power Doppler were performed to evaluate the placental perfusion in 96 pregnant women who came to do the ultrasound routine between 11 and 14 weeks. The placental vascular index (VI), flow index (FI), blood vessels and blood flow index (VFI) by three-dimensional Doppler histogram were calculated. All patients repeated the exam between 16 and 20 weeks. The outcome was scored as normal or preeclamptic. Placental vascular indices including VI, FI and VFI were significantly lower in preeclamptic placentas compared with controls in the study performed in the second trimester (ppower Doppler assessment of placental vascular indices in the second trimester has the potential to detect women at risk for subsequent development of PE. Copyright © 2015 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.

  18. Muscle blood volume assessment during exercise with Power Doppler Ultrasound

    NARCIS (Netherlands)

    Heres, H.M.; Tchang, B.C.Y.; Schoots, T.; Rutten, M.C.M.; van de Vosse, F.N.; Lopata, R.G.P.

    2016-01-01

    Assessment of perfusion adaptation in muscle during exercise can provide diagnostic information on cardiac and endothelial diseases. Power Doppler Ultrasound (PDUS) is known for its feasibility in the non-invasive measurement of moving blood volume (MBV), a perfusion related parameter. In this

  19. Dual beam translator for use in Laser Doppler anemometry

    Science.gov (United States)

    Brudnoy, David M.

    1987-01-01

    A method and apparatus for selectively translating the path of at least one pair of light beams in a Laser Doppler anemometry device whereby the light paths are translated in a direction parallel to the original beam paths so as to enable attainment of spacial coincidence of the two intersection volumes and permit accurate measurements of Reynolds shear stress.

  20. Method and system of doppler correction for mobile communications systems

    Science.gov (United States)

    Georghiades, Costas N. (Inventor); Spasojevic, Predrag (Inventor)

    1999-01-01

    Doppler correction system and method comprising receiving a Doppler effected signal comprising a preamble signal (32). A delayed preamble signal (48) may be generated based on the preamble signal (32). The preamble signal (32) may be multiplied by the delayed preamble signal (48) to generate an in-phase preamble signal (60). The in-phase preamble signal (60) may be filtered to generate a substantially constant in-phase preamble signal (62). A plurality of samples of the substantially constant in-phase preamble signal (62) may be accumulated. A phase-shifted signal (76) may also be generated based on the preamble signal (32). The phase-shifted signal (76) may be multiplied by the delayed preamble signal (48) to generate an out-of-phase preamble signal (80). The out-of-phase preamble signal (80) may be filtered to generate a substantially constant out-of-phase preamble signal (82). A plurality of samples of the substantially constant out-of-phase signal (82) may be accumulated. A sum of the in-phase preamble samples and a sum of the out-of-phase preamble samples may be normalized relative to each other to generate an in-phase Doppler estimator (92) and an out-of-phase Doppler estimator (94).

  1. Research on Fast-Doppler-Broadening of neutron cross sections

    International Nuclear Information System (INIS)

    Li, S.; Wang, K.; Yu, G.

    2012-01-01

    A Fast-Doppler-Broadening method is developed in this work to broaden Continuous Energy neutron cross-sections for Monte Carlo calculations. Gauss integration algorithm and parallel computing are implemented in this method, which is unprecedented in the history of cross section processing. Compared to the traditional code (NJOY, SIGMA1, etc.), the new Fast-Doppler-Broadening method shows a remarkable speedup with keeping accuracy. The purpose of using Gauss integration is to avoid complex derivation of traditional broadening formula and heavy load of computing complementary error function that slows down the Doppler broadening process. The OpenMP environment is utilized in parallel computing which can take full advantage of modern multi-processor computers. Combination of the two can reduce processing time of main actinides (such as 238 U, 235 U) to an order of magnitude of 1∼2 seconds. This new method is fast enough to be applied to Online Doppler broadening. It can be combined or coupled with Monte Carlo transport code to solve temperature dependent problems and neutronics-thermal hydraulics coupled scheme which is a big challenge for the conventional NJOY-MCNP system. Examples are shown to determine the efficiency and relative errors compared with the NJOY results. A Godiva Benchmark is also used in order to test the ACE libraries produced by the new method. (authors)

  2. Cardiac Time Intervals by Tissue Doppler Imaging M-Mode

    DEFF Research Database (Denmark)

    Biering-Sørensen, Tor; Mogelvang, Rasmus; de Knegt, Martina Chantal

    2016-01-01

    PURPOSE: To define normal values of the cardiac time intervals obtained by tissue Doppler imaging (TDI) M-mode through the mitral valve (MV). Furthermore, to evaluate the association of the myocardial performance index (MPI) obtained by TDI M-mode (MPITDI) and the conventional method of obtaining...

  3. Measuring Velocity and Acceleration Using Doppler Shift of a ...

    Indian Academy of Sciences (India)

    to be used to measure its velocity and acceleration. We also apply this method, as an example here, to spectral lines of the blue-shifted jet in micro-quasar SS433 and discuss the intricacies of these measurements. Key words. Doppler effect—measuring velocity and acceleration of the source— jet in SS433. 1. Introduction.

  4. Applications of doppler effect in navigation and oceanography

    Digital Repository Service at National Institute of Oceanography (India)

    Joseph, A.

    The Doppler effect is the change in frequency of the received sound waves/electromagnetic waves when there is a relative motion between the transmitter and the receiver of these waves. This effect is used for diverse applications in different areas...

  5. Doppler Spectrum from Moving Scatterers in a Random Environment

    DEFF Research Database (Denmark)

    Andersen, Jørgen Bach; Nielsen, Jesper Ødum; Pedersen, Gert Frølund

    2009-01-01

    A random non-line-of-sight environment with stationary transmitter and receiver is considered. In such an environment movement of a scatterer will lead to perturbations of the otherwise static channel with a resulting Doppler spectrum. This is quite a general situation in outdoor environments wit...

  6. Noise Studies of Externally Dispersed Interferometry for Doppler Velocimetry

    International Nuclear Information System (INIS)

    Erskine, D J; Edelstein, J; Lloyd, J; Muirhead, P

    2006-01-01

    Externally Dispersed Interferometry (EDI) is the series combination of a fixed-delay field-widened Michelson interferometer with a dispersive spectrograph. This combination boosts the spectrograph performance for both Doppler velocimetry and high resolution spectroscopy. The interferometer creates a periodic comb that multiplies against the input spectrum to create moire fringes, which are recorded in combination with the regular spectrum. Both regular and high-frequency spectral components can be recovered from the data--the moire component carries additional information that increases the signal to noise for velocimetry and spectroscopy. Here we present simulations and theoretical studies of the photon limited Doppler velocity noise in an EDI. We used a model spectrum of a 1600K temperature star. For several rotational blurring velocities 0, 7.5, 15 and 25 km/s we calculated the dimensionless Doppler quality index (Q) versus wavenumber v. This is the normalized RMS of the derivative of the spectrum and is proportional to the photon-limited Doppler signal to noise ratio

  7. THE DOPPLER ECHOGRAPHY – FROM GREEK MYTHOLOGY TO MODERN CARDIOLOGY

    Directory of Open Access Journals (Sweden)

    Diana DĂNIŞOR

    2016-10-01

    Full Text Available The following pages shall demonstrate how the nature of things is made evident through the science of naming, the structure of designation. Through this extensive analysis, I aim at establishing the connection between Greek mythology and modern cardiology by exploring the origin of the word echography and its modern counterpart the Doppler echography.

  8. Radar Micro-Doppler classification of Mini-UAVs

    NARCIS (Netherlands)

    Harmanny, R.L.A.; Prémel-Cabic, G.; Wit, J.J.M.

    2015-01-01

    The radar micro-Doppler signature of a target depends on its micro-motion, i.e., the motion of parts of a target relative to the motion of the target as a whole. These micro-motions are very characteristic considering different target classes, e.g., the slow pendulum-like motion of a bird’s wings

  9. Passive emitter location with Doppler frequency and interferometric measurements

    NARCIS (Netherlands)

    Groot, J.S.; Dam, F.A.M.; Theil, A.

    2008-01-01

    Ground based emitters can be located with a receiver installed on an airborne platform. This paper discusses techniques based on Doppler frequency and differential phase measurements (interferometry). Measurements of the first technique are provided, while we discuss and compare the theoretical

  10. Hydronephrosis and pregnancy: study with Doppler echography. Hidronefrosis y embarazo: estudio mediante ecografia Doppler

    Energy Technology Data Exchange (ETDEWEB)

    Ripolles Gonzalez, T.R.; Ambit Capdevilla, S.; Sanguesa Nebot, C.; Lazaro, S. de; Garcia Vila, J.H.; Belloch Ugarte, V.

    1993-01-01

    An 18-month study was performed to establish the normal intrarenal resistance index during pregnancy, in order to determine whether it differed significantly depending on the week of gestation or the degree of hydronephrosis. For this purpose , the flow velocity waves obtained in right kidney were analyzed in a group of 112 patients on the basis of 209 explorations. The kidneys were classified as grade 0,I,II, or III according to the degree of hydronephrosis. Doppler signal sampling was carried out at the level of the corticomedullary junction. From the results of the study it can be deduced that the index of intrarenal resistance during pregnancy is similar to that of the general population, that there are no significant differences among the groups with different degree of hydronephrosis and that the index does not vary according to the different weeks of gestation. These findings suggest that, during pregnancy, a pathological resistance index in a kidney should not be attributed to the physiological changes associated with normal gestation. (Author) 21 refs.

  11. Settings and artefacts relevant for Doppler ultrasound in large vessel vasculitis

    DEFF Research Database (Denmark)

    Terslev, L; Diamantopoulos, A P; Døhn, U Møller

    2017-01-01

    Ultrasound is used increasingly for diagnosing large vessel vasculitis (LVV). The application of Doppler in LVV is very different from in arthritic conditions. This paper aims to explain the most important Doppler parameters, including spectral Doppler, and how the settings differ from those used...

  12. Predictable progressive Doppler deterioration in IUGR: does it really exist?

    LENUS (Irish Health Repository)

    Unterscheider, Julia

    2013-12-01

    An objective of the Prospective Observational Trial to Optimize Pediatric Health in IUGR (PORTO) study was to evaluate multivessel Doppler changes in a large cohort of intrauterine growth restriction (IUGR) fetuses to establish whether a predictable progressive sequence of Doppler deterioration exists and to correlate these Doppler findings with respective perinatal outcomes.

  13. Pulsed-wave transmitral Doppler do not diagnose moderate acute rejection after heart transplantation

    NARCIS (Netherlands)

    Mannaerts, H. F.; Simoons, M. L.; Balk, A. H.; Tijssen, J.; van der Borden, S. G.; Zondervan, P. E.; Mochtar, B.; Weimar, W.; Roelandt, J. R.

    1993-01-01

    The value of pulsed-wave transmitral Doppler for the diagnosis of moderate acute rejection was examined in a total of 347 Doppler recordings obtained in 32 consecutive cardiac allograft recipients. Serial Doppler examinations (median, 11 per patient; range, 1 to 23) were performed simultaneously

  14. PULSED-WAVE TRANSMITRAL DOPPLER DO NOT DIAGNOSE MODERATE ACUTE REJECTION AFTER HEART-TRANSPLANTATION

    NARCIS (Netherlands)

    MANNAERTS, HF; SIMOONS, ML; BALK, AH; TIJSSEN, J; VANDERBORDEN, SG; ZONDERVAN, PE; MOCHTAR, B; WEIMAR, W; ROELANDT, [No Value

    1993-01-01

    The value of pulsed-wave transmitral Doppler for the diagnosis of moderate acute rejection was examined in a total of 347 Doppler recordings obtained in 32 consecutive cardiac allograft recipients. Serial Doppler examinations (median, 11 per patient; range, 1 to 23) were performed simultaneously

  15. Radar micro-Doppler of wind turbines : Simulation and analysis using rotating linear wire structures

    NARCIS (Netherlands)

    Krasnov, O.A.; Yarovoy, A.

    2015-01-01

    A simple electromagnetic model of wind-turbine's main structural elements as the linear wired structures is developed to simulate the temporal patterns of observed radar return Doppler spectra (micro-Doppler). Using the model, the micro-Doppler for different combinations of the turbines rotation

  16. Doppler ultrasound scan during normal gestation: umbilical circulation

    International Nuclear Information System (INIS)

    Ruiz, T.; Sabate, J.; Martinez-Benavides, M. M.; Sanchez-Ramos, J.

    2002-01-01

    To determine normal umbilical circulation patterns by means of Doppler ultrasound scan in a healthy gestating population without risk factors and with normal perinatal results, and to evaluate any occurring modifications relative to gestational age by obtaining records kept during pregnancy. One hundred and sixteen pregnant women carrying a single fetus have been studied. These women had no risk factors, with both clinical and analytical controls, as well as ultrasound scans, all being normal. There were performed a total of 193 Doppler ultrasound scans between weeks 15 and 41 of gestation, with blood-flow analysis in the arteries and vein of the umbilical cord. The obtained information was correlated with parameters that evaluate fetal well-being (fetal monitoring and/or oxytocin test) and perinatal result (delivery type, birth weight, Apgar score). Statistical analysis was performed with the programs SPSS 6.0.1 for Windows and EPIINFO 6.0.4. With pulsed Doppler, the umbilical artery in all cases demonstrated a biphasic morphology with systolic and diastolic components and without retrograde blood flow. As the gestation period increased, there was observed a progressive decrease in resistance along with an increase in blood-flow velocity during the diastolic phase. The Doppler ultrasound scan is a non-invasive method that permits the hemodynamic study of umbilical blood circulation. A knowledge of normal blood-flow signal morphology, as well as of the normal values for Doppler indices in relation to gestational age would permit us to utilize this method in high-risk pregnancies. (Author) 30 refs

  17. [The use of intraoperative Doppler ultrasound in endoscopic transsphenoidal surgery].

    Science.gov (United States)

    Sharipov, O I; Kutin, M A; Kalinin, P L; Fomichev, D V; Lukshin, V A; Kurnosov, A B

    2016-01-01

    Doppler ultrasound (DUS) has been widely used in neurosurgical practice to diagnose various cerebrovascular diseases. This technique is used in transsphenoidal surgery to identify the localization of intracranial arteries when making an approach or during tumor resection. To identify the cavernous segment of the internal carotid artery (ICA) and/or basilar artery during endoscopic transsphenoidal surgery, we used a combined device on the basis of a click line curette («Karl Storz») and a 16 MHz Doppler probe (Lassamed). The technique was used in 51 patients during both standard transsphenoidal surgery (23 cases) and transsphenoidal tumor resection through an extended approach (28 cases). Doppler ultrasound was used in different situations: to determine a trajectory of the endonasal transsphenoidal approach in the absence of the normal anatomical landmarks (16 cases), to define the limits of safe resection of a tumor located in the laterosellar region (7), and to implement an extended transsphenoidal endoscopic approach (28). Intraoperative Doppler ultrasound enabled identification of the cavernous segment of the internal carotid artery in 45 cases and the basilar artery in 2 cases; a blood vessel was not found in 4 cases. Injury to the cavernous segment of the internal carotid artery was observed only in 1 case. The use of the described combined device in transsphenoidal surgery turned Doppler ultrasound into an important and useful technique for visualization of the ICA within the tumor stroma as well as in the case of the changed skull base anatomy. Its use facilitates manipulations in a deep and narrow wound and enables inspection of the entire surface of the operative field in various planes, thereby surgery becomes safer due to the possibility of maximum investigation of the operative field.

  18. Tissue doppler echocardiography for evaluating left ventricular functions in obese

    Directory of Open Access Journals (Sweden)

    Mecnun Çetin

    2013-03-01

    Full Text Available Objective: The aim of this study was to investigate theimpact of childhood obesity on ventricular functions usingtissue Doppler echocardiography.Materials and methods: The mitral tissue Doppler signalswere recorded in the apical four-chamber view, with thesample volume placed at the lateral walls of mitral annulus.The mitral flow was examined with the sample Pulse Dopplerpositioned parallely to flow just at the orifice of the mitralleaflets. Twenty obese (mean age, 161.5±25.8 monthsand 20 healthy children (mean age, 151.2±33.5 monthswere included to this study.Results: Body mass index (BMI was significantly higherin obese group (30.92±6.87. Isovolumic relaxation time(IVRT which is one of the left ventricular (LV diastolicfunction parameters was 66.10±7.30 ms in obese group,and 58.70±9.06 ms in the control group. IVRT was significantlyhigher in the obese group (p=0.007. In obesegroup, the mitral annulus tissue Doppler E velocity wasdecreased, flow velocity was increased and decrement inEm/Am ratio was significant. We found significant negativecorrelation between BMI and LV Em/Am ratio. Myocardialperformance index (MPI in obese group and control groupwas 0.50±0.07 and 0.41±0.04, respectively (p<0.001.Between MPI and LV Em/Am ratio there was a significantnegative correlation while MPI showed positive correlationwith BMI. In obese group septal and LV posterior wall thicknesswas shown to be significantly increased compared tothe control group (p<0.001.Conclusion: Our findings, may be important for determinationof the relationship between obesity and cardiovascularrisk factors in children. Tissue Doppler echocardiographicimaging may be useful in revealing this relationship.Key words: obesity, doppler echocardiography, ventricular dysfunction

  19. Effectiveness of Pulse Oximetry Versus Doppler for Tourniquet Monitoring.

    Science.gov (United States)

    Wall, Piper L; Buising, Charisse M; Grulke, Lisa; Troester, Alexander; Bianchina, Nicholas; White, Shannon; Freymark, Rosemarie; Hassan, Ali; Hopkins, James W; Renner, Catherine Hackett; Sahr, Sheryl M

    Pulse oximeters are common and include arterial pulse detection as part of their methodology. The authors investigated the possible usefulness of pulse oximeters for monitoring extremity tourniquet arterial occlusion. Tactical Ratcheting Medical Tourniquets were tightened to the least Doppler-determined occluding pressure at mid-thigh or mid-arm locations on one limb at a time on all four limbs of 15 volunteers. A randomized block design was used to determine the placement locations of three pulse oximeter sensors on the relevant digits. The times and pressures of pulsatile signal absences and returns were recorded for 200 seconds, with the tourniquet being tightened only when the Doppler ultrasound and all three pulse oximeters had pulsatile signals present (pulsatile waveform traces for the pulse oximeters). From the first Doppler signal absence to tourniquet release, toe-located pulse oximeters missed Doppler signal presence 41% to 50% of the times (discrete 1-second intervals) and missed 39% to 49% of the pressure points (discrete 1mmHg intervals); fingerlocated pulse oximeters had miss rates of 11% to 15% of the times and 13% to 19% of the pressure points. On toes, the pulse oximeter ranges of sensitivity and specificity for Doppler pulse detection were 71% to 90% and 44% to 51%, and on fingers, the respective ranges were 65% to 77% and 78% to 83%. Use of a pulse oximeter to monitor limb tourniquet effectiveness will result in some instances of an undetected weak arterial pulse being present. If a pulse oximeter waveform is obtained from a location distal to a tourniquet, the tourniquet should be tightened. If a pulsatile waveform is not detected, vigilance should be maintained. 2017.

  20. Acute Effects of Lateral Thigh Foam Rolling on Arterial Tissue Perfusion Determined by Spectral Doppler and Power Doppler Ultrasound.

    Science.gov (United States)

    Hotfiel, Thilo; Swoboda, Bernd; Krinner, Sebastian; Grim, Casper; Engelhardt, Martin; Uder, Michael; Heiss, Rafael U

    2017-04-01

    Hotfiel, T, Swoboda, B, Krinner, S, Grim, C, Engelhardt, M, Uder, M, and Heiss, R. Acute effects of lateral thigh foam rolling on arterial tissue perfusion determined by spectral Doppler and power Doppler ultrasound. J Strength Cond Res 31(4): 893-900, 2017-Foam rolling has been developed as a popular intervention in training and rehabilitation. However, evidence on its effects on the cellular and physiological level is lacking. The aim of this study was to assess the effect of foam rolling on arterial blood flow of the lateral thigh. Twenty-one healthy participants (age, 25 ± 2 years; height, 177 ± 9 cm; body weight, 74 ± 9 kg) were recruited from the medical and sports faculty. Arterial tissue perfusion was determined by spectral Doppler and power Doppler ultrasound, represented as peak flow (Vmax), time average velocity maximum (TAMx), time average velocity mean (TAMn), and resistive index (RI), and with semiquantitative grading that was assessed by 4 blindfolded investigators. Measurement values were assessed under resting conditions and twice after foam rolling exercises of the lateral thigh (0 and 30 minutes after intervention). The trochanteric region, mid portion, and distal tibial insertion of the lateral thigh were representative for data analysis. Arterial blood flow of the lateral thigh increased significantly after foam rolling exercises compared with baseline (p ≤ 0.05). We detected a relative increase in Vmax of 73.6% (0 minutes) and 52.7% (30 minutes) (p power Doppler scores at all portions revealed increased average grading of 1.96 after intervention and 2.04 after 30 minutes compared with 0.75 at baseline. Our results may contribute to the understanding of local physiological reactions to self-myofascial release.

  1. Augmented Reality Based Doppler Lidar Data Visualization: Promises and Challenges

    Science.gov (United States)

    Cherukuru, N. W.; Calhoun, R.

    2016-06-01

    Augmented reality (AR) is a technology in which the enables the user to view virtual content as if it existed in real world. We are exploring the possibility of using this technology to view radial velocities or processed wind vectors from a Doppler wind lidar, thus giving the user an ability to see the wind in a literal sense. This approach could find possible applications in aviation safety, atmospheric data visualization as well as in weather education and public outreach. As a proof of concept, we used the lidar data from a recent field campaign and developed a smartphone application to view the lidar scan in augmented reality. In this paper, we give a brief methodology of this feasibility study, present the challenges and promises of using AR technology in conjunction with Doppler wind lidars.

  2. Assessment of right ventricular systolic function by tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Kjærgaard, Jesper

    2012-01-01

    This thesis summarizes a series of studies performed in order to assess the clinical usefulness of a novel echocardiographic technology that allows non-invasive assessment of regional right ventricular myocardial velocities and deformation: tissue Doppler echocardiography. While the technology...... is a promising tool for improving our understanding of right ventricular hemodynamics, several aspects of the technology must be evaluated. The accuracy and reproducibility of the technology is evaluated in vitro, and normal values, impact of changes in loading of the right ventricle, response to exercise...... on right ventricular hemodynamics: pulmonary embolism, Arrhythmogenic right ventricular cardiomyopathy and pulmonary regurgitation, the latter in an animal model. The conclusions of the thesis are: Color tissue Doppler echocardiography accurately measures velocities, SR and strain in vitro. No systematic...

  3. Doppler Lidar Vertical Velocity Statistics Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Newsom, R. K. [DOE ARM Climate Research Facility, Washington, DC (United States); Sivaraman, C. [DOE ARM Climate Research Facility, Washington, DC (United States); Shippert, T. R. [DOE ARM Climate Research Facility, Washington, DC (United States); Riihimaki, L. D. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-07-01

    Accurate height-resolved measurements of higher-order statistical moments of vertical velocity fluctuations are crucial for improved understanding of turbulent mixing and diffusion, convective initiation, and cloud life cycles. The Atmospheric Radiation Measurement (ARM) Climate Research Facility operates coherent Doppler lidar systems at several sites around the globe. These instruments provide measurements of clear-air vertical velocity profiles in the lower troposphere with a nominal temporal resolution of 1 sec and height resolution of 30 m. The purpose of the Doppler lidar vertical velocity statistics (DLWSTATS) value-added product (VAP) is to produce height- and time-resolved estimates of vertical velocity variance, skewness, and kurtosis from these raw measurements. The VAP also produces estimates of cloud properties, including cloud-base height (CBH), cloud frequency, cloud-base vertical velocity, and cloud-base updraft fraction.

  4. Doppler reflectometry for the investigation of poloidally propagating density perturbations

    International Nuclear Information System (INIS)

    Hirsch, M.; Baldzuhn, J.; Kurzan, B.; Holzhauer, E.

    1999-01-01

    A modification of microwave reflectometry is discussed where the direction of observation is tilted with respect to the normal onto the reflecting surface. The experiment is similar to scattering where a finite resolution in k-space exists but keeps the radial localization of reflectometry. The observed poloidal wavenumber is chosen by Bragg's condition via the tilt angle and the resolution in k-space is determined by the antenna pattern. From the Doppler shift of the reflected wave the poloidal propagation velocity of density perturbations is obtained. The diagnostic capabilities of Doppler reflectometry are investigated using full wave code calculations. The method offers the possibility to observe changes in the poloidal propagation velocity of density perturbations and their radial shear with a temporal resolution of about 10μs. (authors)

  5. Doppler broadening measurements in FRX-C/LSM

    International Nuclear Information System (INIS)

    Baron, M.H.; Chrien, R.E.

    1989-01-01

    Measurements obtained in situ during field reversed configuration (FRC) formation show that the Doppler broadening ion temperature T CV is larger by a factor of two or more than the ion temperature T i derived from pressure balance and Thomson scattering. After a time comparable to an ion-ion equilibrium time, T CV and T i come into agreement with each other. An exception to this picture occurs in the lowest fill pressure condition (2 mtorr), for which T CV > T i is maintained throughout the FRC lifetime. Earlier Doppler broadening measurements in FRX-B and FRX-C also showed persistent, anomalously high T CV at low fill pressure. The initially high values of T CV are probably caused by convective motion generated by the radial implosion. The low fill pressure results suggest an enhanced ohmic power input to the carbon ions. 7 refs., 3 figs

  6. Aircraft Wake Vortex Measurement with Coherent Doppler Lidar

    Directory of Open Access Journals (Sweden)

    Wu Songhua

    2016-01-01

    Full Text Available Aircraft vortices are generated by the lift-producing surfaces of the aircraft. The variability of near-surface conditions can change the drop rate and cause the cell of the wake vortex to twist and contort unpredictably. The pulsed Coherent Doppler Lidar Detection and Ranging is an indispensable access to real aircraft vortices behavior which transmitting a laser beam and detecting the radiation backscattered by atmospheric aerosol particles. Experiments for Coherent Doppler Lidar measurement of aircraft wake vortices has been successfully carried out at the Beijing Capital International Airport (BCIA. In this paper, the authors discuss the Lidar system, the observation modes carried out in the measurements at BCIA and the characteristics of vortices.

  7. Multipoint photonic doppler velocimetry using optical lens elements

    Science.gov (United States)

    Frogget, Brent Copely; Romero, Vincent Todd

    2014-04-29

    A probe including a fisheye lens is disclosed to measure the velocity distribution of a moving surface along many lines of sight. Laser light, directed to the surface and then reflected back from the surface, is Doppler shifted by the moving surface, collected into fisheye lens, and then directed to detection equipment through optic fibers. The received light is mixed with reference laser light and using photonic Doppler velocimetry, a continuous time record of the surface movement is obtained. An array of single-mode optical fibers provides an optic signal to an index-matching lens and eventually to a fisheye lens. The fiber array flat polished and coupled to the index-matching lens using index-matching gel. Numerous fibers in a fiber array project numerous rays through the fisheye lens which in turn project many measurement points at numerous different locations to establish surface coverage over a hemispherical shape with very little crosstalk.

  8. Normal Doppler velocimetry of renal vasculature in Persian cats.

    Science.gov (United States)

    Carvalho, Cibele F; Chammas, Maria C

    2011-06-01

    Renal diseases are common in older cats. Decreased renal blood flow may be the first sign of dysfunction and can be evaluated by Doppler ultrasound. But previous studies suggest that the resistive index (RI) has a low sensitivity for detecting renal disease. Doppler waveforms of renal and intrarenal arteries demonstrate decreased blood flow before there are any changes in the RI. The purpose of this study was to evaluate the normal Doppler flowmetrics parameters of renal arteries (RAs), interlobar arteries (IAs) and abdominal aorta (AO) in adult healthy, Persian cats. Twenty-five Persian cats (13 females and 12 males with mean age of 30 months and an age range 12-60 months) with normal clinical examinations and biochemical tests and normal systemic blood pressure were given B-mode ultrasonographies in order to exclude all nephropathies, including polycystic kidney disease. All measurements were performed on both kidneys. Both kidneys (n=50) were examined by color mapping of the renal vasculature. Pulsed Doppler was used to examine both RAs, the IAs at cranial, middle and caudal sites, and the AO. The RI was calculated for all of the vessels. Early systolic acceleration (ESA) of RA and IA was obtained with Doppler spectral analysis. Furthermore, the ratio indices between RA/AO, and IA/RA velocities were calculated. The mean values of peak systolic velocity (PSV) and the diameter for AO were 53.17±13.46 cm/s and 0.38±0.08 cm, respectively. The mean RA diameter for all 50 kidneys was 0.15±0.02 cm. Considering the velocimetric values in both RAs, the mean PSV and RI that were obtained were 41.17±9.40 cm/s and 0.54±0.07. The RA had a mean ESA of 1.12±1.14 m/s(2) and the calculated upper limit of the reference value was 3.40 m/s(2). The mean renal-aortic ratio was 0.828±0.296. The IA showed PSV and RI values of 32.16±9.33 cm/s and 0.52±0.06, respectively. The mean ESA of all IAs was 0.73±0.61 m/s(2). The calculated upper limit of the reference value was 2.0m

  9. Left coronary arterial blood flow: Noninvasive detection by Doppler US

    International Nuclear Information System (INIS)

    Gramiak, R.; Holen, J.; Moss, A.J.; Gutierrez, O.H.; Picone, A.L.; Roe, S.A.

    1986-01-01

    Continuous wave (CW) and pulsed Doppler ultrasound studies with spectral analysis were used to detect the left coronary arterial blood flow in patients who were undergoing routine echocardiography. The pulmonary artery is a stable ultrasonic landmark from which detection of the blood flow can be effected. The left coronary artery can be distinguished by its blood flow toward the cardiac apex and by specific, functional flow features. Flow patterns vary among the left main, circumflex, and anterior descending arteries; patterns also vary with respiration cycles. In the present study, coronary arterial blood flow was detected in 58 of 70 patients (83%). Findings were validated by selectively injecting an agitated saline contrast medium into the left coronary artery and, in another study, by comparing human Doppler phasic flow waveforms with electromagnetic flowmeter recordings obtained in dogs

  10. Cerebrovascular reactivity in migraineurs as measured by transcranial Doppler

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, T.D.; Harpold, G.J. (Alabama Univ., Birmingham, AL (USA). School of Medicine); Troost, B.T. (Bowman Gray School of Medicine, Winston-Salem, NC (USA))

    1990-04-01

    Transcranial Doppler ultrasound is a relatively new diagnostic modality which allows the non-invasive assessment of intracranial circulation. A total of 10 migraine patients were studied and compared to healthy controls without headaches. Migraineurs during the headache-free interval demonstrated excessive cerebrovascular reactivity to CO{sub 2}, evidenced by an increase in middle cerebral artery blood flow velocity of 47% {plus minus} 15% compared to 28% {plus minus} 14% in controls. Differences between the two study groups revealed no significant decrease in middle cerebral artery blood flow velocity with hypocapnia. However, the differences between middle cerebral artery blood flow velocity during hyperventilation and CO{sub 2} inhalation were significantly different comparing migraineurs and controls. Instability of the baseline blood flow velocities was also noted in migraineurs during the interictal period. Characteristics which may allow differentiation of migraineurs from other headache populations could possibly be obtained from transcranial Doppler ultrasound flow studies. 24 refs., 2 tabs.

  11. Cerebrovascular reactivity in migraineurs as measured by transcranial Doppler

    International Nuclear Information System (INIS)

    Thomas, T.D.; Harpold, G.J.

    1990-01-01

    Transcranial Doppler ultrasound is a relatively new diagnostic modality which allows the non-invasive assessment of intracranial circulation. A total of 10 migraine patients were studied and compared to healthy controls without headaches. Migraineurs during the headache-free interval demonstrated excessive cerebrovascular reactivity to CO 2 , evidenced by an increase in middle cerebral artery blood flow velocity of 47% ± 15% compared to 28% ± 14% in controls. Differences between the two study groups revealed no significant decrease in middle cerebral artery blood flow velocity with hypocapnia. However, the differences between middle cerebral artery blood flow velocity during hyperventilation and CO 2 inhalation were significantly different comparing migraineurs and controls. Instability of the baseline blood flow velocities was also noted in migraineurs during the interictal period. Characteristics which may allow differentiation of migraineurs from other headache populations could possibly be obtained from transcranial Doppler ultrasound flow studies. 24 refs., 2 tabs

  12. Altered doppler flow patterns in cirrhosis patients: An overview

    Energy Technology Data Exchange (ETDEWEB)

    Iranpour, Pooya; Lall, Chandana; Houshyar, Roozbeh; Helmy, Mohammad; Yang, Albert; Ward, Garrett; Goodwin, Scott C. [Dept. of Radiology, University of California Irvine, Orange (United States); Choi, Joon Il [Dept. of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2016-01-15

    Doppler ultrasonography of the hepatic vasculature is an integral part of evaluating precirrhotic and cirrhotic patients. While the reversal of the portal venous flow is a well-recognized phenomenon, other flow patterns, although not as easily understood, may play an important role in assessing the disease status. This article discusses the different characteristic flow patterns observed from the portal vein, hepatic artery, and hepatic vein in patients with liver cirrhosis or related complications and procedures. Knowledge of these different flow patterns provides additional information that may reinforce the diagnosis of cirrhosis, help in staging, and offer prognostic information for determining the direction of therapy. Doppler ultrasonography is invaluable when liver transplantation is being considered and aids in the diagnosis of cirrhosis and portal hypertension.

  13. Performance evaluation of a thermal Doppler Michelson interferometer system.

    Science.gov (United States)

    Mani, Reza; Dobbie, Steven; Scott, Alan; Shepherd, Gordon; Gault, William; Brown, Stephen

    2005-11-20

    The thermal Doppler Michelson interferometer is the primary element of a proposed limb-viewing satellite instrument called SWIFT (Stratospheric Wind Interferometer for Transport studies). SWIFT is intended to measure stratospheric wind velocities in the altitude range of 15-45 km. SWIFT also uses narrowband tandem etalon filters made of germanium to select a line out of the thermal spectrum. The instrument uses the same technique of phase-stepping interferometry employed by the Wind Imaging Interferometer onboard the Upper Atmosphere Research Satellite. A thermal emission line of ozone near 9 microm is used to detect the Doppler shift due to winds. A test bed was set up for this instrument that included the Michelson interferometer and the etalon filters. For the test bed work, we investigate the behavior of individual components and their combination and report the results.

  14. Ultrasonic Doppler measurement of renal artery blood flow

    Science.gov (United States)

    Freund, W. R.; Meindl, J. D.

    1975-01-01

    An extensive evaluation of the practical and theoretical limitations encountered in the use of totally implantable CW Doppler flowmeters is provided. Theoretical analyses, computer models, in-vitro and in-vivo calibration studies describe the sources and magnitudes of potential errors in the measurement of blood flow through the renal artery, as well as larger vessels in the circulatory system. The evaluation of new flowmeter/transducer systems and their use in physiological investigations is reported.

  15. Temperature and Doppler coefficients of various space nuclear reactors

    International Nuclear Information System (INIS)

    Mughabghab, S.F.; Ludewig, H. Schmidt, E.

    1993-01-01

    Temperature and Doppler feedback effects for a Particle Bed Reactor (PBR) designed to operate as a propulsion reactor are investigated. Several moderator types and compositions fuel enrichments and reactor sizes are considered in this study. From this study it could be concluded that a PBR can be configured which has a negative prompt feedback, zero coolant worth, and a small positive to zero moderator worth. This reactor would put the lowest demands on the control system

  16. Doppler Processing with Ultra-Wideband (UWB) Radar Revisited

    Science.gov (United States)

    2018-01-01

    REPORT TYPE Technical Note 3. DATES COVERED (From - To) December 2017 4. TITLE AND SUBTITLE Doppler Processing with Ultra-Wideband (UWB) Radar...unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT This technical note revisits previous work performed at the US Army Research Laboratory related to...target considered previously is proportional to a delayed version of the transmitted signal, up to a complex constant factor. We write the received

  17. Detection of gravitational radiation by the Doppler tracking of spacecraft

    International Nuclear Information System (INIS)

    Mashhoon, B.

    1979-01-01

    It has been suggested that the residual Doppler shift in the precision electromagnetic tracking of spacecraft be used to search for gravitational radiation that may be incident on the Earth-spacecraft system. The influence of a gravitational wave on the Doppler shift is calculated, and it is found that the residual shift is dominated by two terms: one is due to the passage of electromagnetic waves through the gravitational radiation field, and the other depends on the change in the relative velocity of the Earth and the spacecraft caused by the external wave. A detailed analysis is given of the influence of gravitational radiation on a binary system with an orbital size small compared to the wavelength of the incident radiation. It is shown that, as a consequence of the interaction with the external wave, the system makes a transition from one Keplerian orbit into another which, in general, has a different energy and angular momentum. It is therefore proposed to search for such effects in the solar system. Observations of the orbit of an artificial Earth satellite, the lunar orbit, and especially the planetary orbits offer exciting possibilities for the detection of gravitational waves of various wavelengths. From the results of the lunar laser ranging experiment and the range measurement to Mars, certain interesting limits may be established on the frequency of incidence of gravitational waves of a given flux on the Earth-Moon and the Earth-Mars systems. This is followed by a brief and preliminary analysis of the possibility of detecting gravitational radiation by measuring a residual secular Doppler shift in the satellite-to-satellite Doppler tracking of two counterorbiting drag-free spacecraft around the Earth as in the Van Patten-Everitt experiment

  18. Role of uterine artery doppler ultrasound in predicting preeclampsia primigravida

    International Nuclear Information System (INIS)

    Awan, F.; Ullah, H.

    2016-01-01

    Objective: To find the accuracy of uterine artery diastolic notching during the second trimester of pregnancy in predicting pre-eclampsia in primigravida patients. Study Design: Descriptive cross sectional study. Place and Duration of Study: Armed Forces Institute of Radiology and Imaging (AFIRI) Rawalpindi; six months duration from 30 Nov 2012 to 31 May 2013. Material and Methods: This study included 199 primigravida women with singleton pregnancy having diastolic notch in uterine arteries between 20 to 23 weeks of gestation. All patients were examined by both grey scale and doppler ultrasonography. Uterine arteries were evaluated with doppler near the point where they crossed the external iliac arteries. The patient was included in study if the presence of diastolic notch was demonstrated. Clinical follow up in gynae and obs department continued throughout the pregnancy to see if they developed preeclampsia. The data were recorded on a previously prepared proforma and analyzed with SPSS 21. Results: The accuracy of uterine artery doppler ultrasound in identifying women who later developed preeclampsia was 48.24 percent. The frequency of pre-eclampsia with bilateral notch was significantly high in the primigravid of younger age as compare to the primigravid of the older group (p=0.001). The difference in frequency of developing pre-eclampsia with bilateral notch when compared among 20 to 21 week gestational age and 22 to 23 weeks gestational age was statistically insignificant. Conclusion: Uterine artery diastolic notching between 20 and 23 weeks of gestation is an important risk factor for developing pre-eclampsia. This doppler parameter should, therefore, be included in the risk evaluation for gestational hypertension. (author)

  19. Fourier and wavelet analysis of skin laser doppler flowmetry signals

    OpenAIRE

    Qi, Wei

    2011-01-01

    ObjectiveThis thesis examines the measurement of skin microvascular blood flows from Laser Doppler Flowmetry (LDF) signals. Both healthy subjects and those with features of the metabolic syndrome are studied using signal processing techniques such as the Fourier and Wavelet transforms. An aim of this study is to investigate whether change in blood flow at rest can be detected from the spectral content of the processed signals in the diferent subject groups. Additionally the effect of insulin ...

  20. Temperature and Doppler Coefficients of Various Space Nuclear Reactors

    Science.gov (United States)

    Mughabghab, Said F.; Ludewig, Hans; Schmidt, Eldon

    1994-07-01

    Temperature and Doppler feedback effects for a Particle Bed Reactor (PBR) designed to operate as a propulsion reactor are investigated. Several moderator types and compositions fuel enrichments and reactor sizes are considered in this study. From this study it could be concluded that a PBR can be configured which has a negative prompt feedback, zero coolant worth, and a small positive to zero moderator worth. This reactor would put the lowest demands on the control system.

  1. Analytical theory of Doppler reflectometry in slab plasma model

    Energy Technology Data Exchange (ETDEWEB)

    Gusakov, E.Z.; Surkov, A.V. [Ioffe Institute, Politekhnicheskaya 26, St. Petersburg (Russian Federation)

    2004-07-01

    Doppler reflectometry is considered in slab plasma model in the frameworks of analytical theory. The diagnostics locality is analyzed for both regimes: linear and nonlinear in turbulence amplitude. The toroidal antenna focusing of probing beam to the cut-off is proposed and discussed as a method to increase diagnostics spatial resolution. It is shown that even in the case of nonlinear regime of multiple scattering, the diagnostics can be used for an estimation (with certain accuracy) of plasma poloidal rotation profile. (authors)

  2. Laser methods of. gamma. spectroscopy without Doppler broadening

    Energy Technology Data Exchange (ETDEWEB)

    Letokhov, V S [AN SSSR, Moscow. Inst. Spektroskopii

    1976-01-01

    Some new ideas and methods being conceived in a boundary area between atomic-molecular and nuclear physics are discussed. The recent progress with lasers tunable in the UV, visible, and IR should make the realization of these methods quite possible. There are at least two effects that link atomic and molecular transitions with nuclear transitions: they are the recoil effect and the Doppler effect.

  3. Choroid metastasis of papillary thyroid carcinoma. Color doppler ultrasound study

    International Nuclear Information System (INIS)

    Ganado, T.; Torre, S. de la; Contreras, E.; Hernandez, J.

    1997-01-01

    The most common causes of intraocular metastases are breast and lung cancers, although many other neoplasms can metastasize to the eye. Most of the metastases are located in the posterior pole and the choroid is more often involved than the retina. We present a case of a choroidal metastasis from a papillary carcinoma of the thyroid, associated with a massive subretinal hemorrhage. Findings with color Doppler ultrasound are emphasized. (Author) 9 refs

  4. Umbilical artery doppler abnormalities and associated factors in ...

    African Journals Online (AJOL)

    Critically ill patients and those in active phase of labour or premature rupture of membranes were excluded. Results: The overall prevalence of UA Doppler abnormalities was 31.6%. High RI, high S/D ratio, AEDV and RF were found in 25.8%, 31.6%, 7.7% and 4.5% of the population respectively. Key factors associated with ...

  5. Prediction of cerebrovascular reserve by the MRI and doppler ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hui Joong; Kim, Yong Sun [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2005-07-15

    We investigated acute stroke patterns on diffusion weighted images and with doppler ultrasonography studies of ICA and MCA steno-occlusive diseases in order to predict the cerbrovascular reserve (CVR), as was measured by acetazolamide (ACZ)-challenged Tc-99m ECD brain perfusion SPECT. A retrospective analysis was performed of 76 patients who underwent MRI/MRA, ACZ-challenged Tc-99m ECD brain perfusion SPECT, and carotid and vertebral artery Doppler sonography. After dividing these patients into four groups-MCA and ICA ateno-occlusions, we analyzed the relationship between the CVR and topologic MR patterns and the flow volume, as was measured by Doppler sonography. The CVRs were preserved in 26 of 76 patients. The CVRs were impaired in those cases of occlusion that were detected on MRA and also by the pattern of the territorial involvement on the diffusion weighted image ({rho} < 0.05, x{sup 2} test). Yet in cases of preserved CVRs, the flow volume of the contralateral ICA, the anterior circulation, and the total cerebral flow volume were increased, as was checked by Doppler sonography ({rho} < 0.05, t-test). As calculated by logistic regression analysis, the accuracy for predicting the preserved CVR by using the statistically significant variables was 78%. We believe that the MRI-SPECT correlation study was helpful for understanding the hemodynamics and topographic patterns of ischemia in patients with ICA and MCA steno-occlusive disease, and that the flow volume measurement, which was done by using duplex US, was useful for predicting the CVR.

  6. Porøse materialer

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place

    2000-01-01

    Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM).......Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM)....

  7. Gestational trophoblastic neoplasia: efficacy of color doppler ultrasound

    International Nuclear Information System (INIS)

    Song, Sun Wha; Jee, Won Hee; Choe, Bo Young; Byun, Jae Young; Choi, Byung Gil; Shinn, Kyung Sub

    1997-01-01

    To evaluate the efficacy of color Doppler ultrasound (US) in the diagnosis of gestational trophoblastic neoplasia (GTN). Intralesional color flows and resistive index (RI) on color Doppler US were prospectively analyzed in 21 consecutive suspected GTN cases. RI of the intralesional artery was investigated on the basis of the presence or absence of mass and metastasis. Correlation between RI of intralesional artery and urinary β-hCG was also investigated. Intralesional color flows were identified in 15 patients with GTN. On operation, intralesional color flows were observed in one of two patients in whom the presence of completely necrotic tissue was confirmed. Intralesional color flows, however, were not detected in four patients who were proved not to be GTN sufferers. Sensitivity, specificity, accuracy, positive and negative predictive values, and accuracy were 100%, 83%, 95%, 94% and 100%, respectively. Significant correlation between RI of the intralesional artery and urinary β-hCG was not established (p=0.49, r=0.19). RI of this artery was not substantially different between groups with and without mass, and between groups with and without metastasis (p=0.32, p=0.82). The current study demonstrates that color Doppler US is a sensitive and useful method for the diagnosis of GTN

  8. On the Fly Doppler Broadening Using Multipole Representation

    International Nuclear Information System (INIS)

    Khassenov, Azamat; Choi, Sooyoung; Lee, Deokjung

    2015-01-01

    On the Fly Doppler broadening is the technique to avoid pre-generation of the microscopic cross section, in other words, reduce the amount of storage. Currently, there are different types of formalisms used by NJOY code to generate reaction cross section and accomplish its Doppler broadening. Single-Level Breit-Wigner (SLBW) formalism is limited to well-separated resonances, in other words, it does not consider interference between energy levels. Multi-Level Breit- Wigner formalism (MLBW) was tested as the candidate for the cross section generation in the Monte Carlo code, which is under development in UNIST. According to the results, MLBW method requires huge amount of computational time to produce cross section at certain energy point. Reich-Moore (RM) technique can generate only 0K cross section, which means that it cannot produce broaden cross section directly from resonance parameters. The first step was to convert resonance parameters given in nuclear data file into multipoles. MPR shows very high potential to be used as the formalism in the on-the-fly Doppler broadening module of MCS. One of the main reasons is that comparison of the time cost shown in Table IV supports application of multipole representation

  9. Echobiometrics kidney and renal artery triplex doppler of canine fetuses

    Directory of Open Access Journals (Sweden)

    M.A.R. Feliciano

    2014-04-01

    Full Text Available The aim of this study was to assess the sogographic parameters and biometry of canine fetal kidneys using the B mode, and to determinate the vascular index of the fetal renal arteries using the Doppler Triplex. Twenty four Shi-tzu and Pug, weighting between 4 and 10kg, aging between 4 and 6 years old were evaluated. The B mode, the fetal renal echobiometry and regularity of the renal surface, echotexture and cortex:medular ratio were evaluated during the 5th, 6th, 7th and 8th weeks of pregnancy. At the same time point of the B mode evaluation, the Doppler Triplex was carried out to assess the sistolic peak velocity (SPV, end diastolic velocity (EDV, vascular resistive (RI and pulsatility index (PI. B mode revealed no fetal renal abnormalities and echobiometry showed important measurements during fetal development (P0.05. B mode and Doppler Triplex were important tools for the assessment of fetal renal development, using echobiometry and renal arterial index in canie fetuses.

  10. A Wearable Transcranial Doppler Ultrasound Phased Array System.

    Science.gov (United States)

    Pietrangelo, Sabino J; Lee, Hae-Seung; Sodini, Charles G

    2018-01-01

     Practical deficiencies related to conventional transcranial Doppler (TCD) sonography have restricted its use and applicability. This work seeks to mitigate several such constraints through the development of a wearable, electronically steered TCD velocimetry system, which enables noninvasive measurement of cerebral blood flow velocity (CBFV) for monitoring applications with limited operator interaction. A highly-compact, discrete prototype system was designed and experimentally validated through flow phantom and preliminary human subject testing. The prototype system incorporates a custom two-dimensional transducer array and multi-channel transceiver electronics, thereby facilitating acoustic beamformation via phased array operation. Electronic steering of acoustic energy enables algorithmic system controls to map Doppler power throughout the tissue volume of interest and localize regions of maximal flow. Multi-focal reception permits dynamic vessel position tracking and simultaneous flow velocimetry over the time-course of monitoring. Experimental flow phantom testing yielded high correlation with concurrent flowmeter recordings across the expected range of physiological flow velocities. Doppler power mapping has been validated in both flow phantom and preliminary human subject testing, resulting in average vessel location mapping times testing. A wearable prototype CBFV measurement system capable of autonomous vessel search and tracking has been presented. Although flow phantom and preliminary human validation show promise, further human subject testing is necessary to compare velocimetry data against existing commercial TCD systems. Additional human subject testing must also verify acceptable vessel search and tracking performance under a variety of subject populations and motion dynamics-such as head movement and ambulation.

  11. Study of retrobulbar hemodynamics in diabetes via color doppler ultrasound

    Directory of Open Access Journals (Sweden)

    Wei Chen

    2014-09-01

    Full Text Available AIM: To explore the changes of retrobulbar hemodynamics in diabetes via color doppler ultrasound. METHODS: Totally 80 patients(160 eyeswith eye diseases in type 2 diabetes from June 2010 to May 2013 in our hospital were enrolled as research group. By fundus photography and direct ophthalmoscopy, patients were assigned to diabetes without retinopathy group(DNR subgroup, non-proliferative diabetic retinopathy group(NPDR subgroupand proliferative diabetic retinopathy group(PDR subgroup. Of 60 healthy patients(120 eyesover the same period were chosen as control group. The doppler parameters of central retinal artery(CRA, posterior ciliary artery(PCAand ophthalmic artery(OAwere measured.RESULTS: There were significant differences on circulatory parameters of CRA, PCA and OA between both groups(PPPCONCLUSION: The monitoring of retinal blood flow and analysis of blood spectrum morphology via color doppler ultrasound can effectively evaluate the degree of diabetic retinopathy lesions, especially before DR vascular disease. Early detection can reveal the hemodynamic change pattern of DR, facilitating the prevention of diabetic eye complications and improvement of the quality of life.

  12. [Usefulness of transvaginal Doppler color in ovarian neoplasms diagnosis].

    Science.gov (United States)

    Muñoz, H; Martínez, L; Parra, M; Cunill, E; Polanco, M; Leible, S; Romero, C

    1993-01-01

    The vascular resistant evaluation by Doppler waveform is a method used in clinic and research. The neoplastic malignant has an increased growth with an increased amount of neomalignant vessels. The presence of these vessels produce an increase of the transversal section area from the tumoral vascular system, therefore there is a decrease in the vascular resistance. The main objective of this work is to show the usefulness of Doppler waveform as predictor factor of malignity in ovary tumors. Eighteen patients with tumoral mass in the ovary were studied. They were between 21 and 67 years old (mean = 43). The tumoral volume and the flow resistance of blood vessels which irrigated those tumoral mass were evaluated by transvaginal ultrasound with color and pulsed Doppler. The pulsatility index (SD/media) was used. The Chi cuadrado test was used to evaluate the results. The results show the presence of six malignant tumors, three of them with low malignicity and the presence of twelve benign tumors. The age of the patients between both groups (malignant and benign tumors) were significant different (40.7 versus 52 years old, p < 0.001). The mean tumoral volume was 65 ml, with a range of 17 to 225 ml in the group of patients with benign tumors and the mean tumoral volume from patients with malignant tumors was 951 ml with a range of 141 to 3142 ml. The difference in the tumoral in both groups was significative with p < 0.001.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. [Current role of color Doppler ultrasound in acute renal failure].

    Science.gov (United States)

    Bertolotto, M; Quaia, E; Rimondini, A; Lubin, E; Pozzi Mucelli, R

    2001-01-01

    Acute Renal Failure (ARF) is characterized by a rapid decline of the glomerular filtration rate, due to hypotension (prerenal ARF), obstruction of the urinary tract (post-renal ARF) or renal parenchymal disease (renal ARF). The differential diagnosis among different causes of ARF is based on anamnesis, clinical symptoms and laboratory data. Usually ultrasound (US) is the only imaging examination performed in these patients, because it is safe and readily available. In patients with ARF gray scale US is usually performed to rule out obstruction since it is highly sensitive to recognize hydronephrosis. Patients with renal ARF have no specific changes in renal morphology. The size of the kidneys is usually normal or increased, with smooth margins. Detection of small kidneys suggests underlying chronic renal pathology and worse prognosis. Echogenicity and parenchymal thickness are usually normal, but in some cases there are hyperechogenic kidneys, increased parenchymal thickness and increased cortico-medullary differentiation. Evaluation of renal vasculature with pulsed Doppler US is useful in the differential diagnosis between prerenal ARF and acute tubular necrosis (ATN), and in the diagnosis of renal obstruction. Latest generation US apparatus allow color Doppler and power Doppler evaluation of renal vasculature up to the interlobular vessels. A significant, but non specific, reduction in renal perfusion is usually appreciable in the patients with ARF. There are renal pathologic conditions presenting with ARF in which color Doppler US provides more specific morphologic and functional information. In particular, color Doppler US often provides direct or indirect signs which can lead to the right diagnosis in old patients with chronic renal insufficiency complicated with ARF, in patients with acute pyelonephritis, hepatic disease, vasculitis, thrombotic microangiopathies, and in patients with acute thrombosis of the renal artery and vein. Contrast enhanced US is

  14. Accuracy of doppler ultrasound in diagnosis of endometrial carcinoma

    International Nuclear Information System (INIS)

    Batool, S.; Raza, S.; Manzur, S.

    2013-01-01

    Objective: To determine the accuracy of Doppler ultrasound in the diagnosis of endometrial carcinoma in patients presenting with post-menopausal bleeding while taking histopathological findings as the gold standard. Methods: The cross-sectional study was done at the Department of Radiology, Bahawal Victoria Hospital, Bahawalpur, from April 1 to September 30, 2009, and comprised 128 patients above 50 years of age having history of post-menopausal bleeding and who were referred to the department. Name, age and hospital registration number were recorded on a proforma. Doppler ultrasound was performed and endometrial thickness and uterine artery resistive index were recorded on transabdominal ultrasonography. Patients with endometrial thickness of more than 5mm and uterine artery resistive index of less than 0.7 were considered to be having endometrial carcinoma. Histopathology findings were also recorded using the hospital registration number of the patient. The findings of Doppler ultrasound scan were validated with the findings of histopathology. Results: Of the 128 patients, 48 (37.5%) were between the ages of 51 and 55 years; 46 (35.93%) were in the 56-60 age group; and 34 (26.57%) were over 65 years. On the basis of Doppler ultrasound findings, 106 (82.8%) patients were diagnosed as having endometrial carcinoma, while 22 (17.19%) were declared negative. Ultrasonography results were compared with histopathology findings. The percentages of true positive, true negative, false positive and false negative were calculated. There were 103 (80.47%) true positive; 12 (9.37%) false positive; 10 (7.81%) true negative; and 3 (2.35%) false negative. Specificity, sensitivity, positive predictive value and negative predictive value were found to be 97.16%, 76%, 89.56% and 76.92% respectively. Conclusion: The use of Doppler ultrasonography in non-invasive diagnosis of endometrial carcinoma in patients presenting with post-menopausal bleeding was quite useful with good

  15. Doppler ultrasound study of penis in men with systemic sclerosis: a correlation with Doppler indices of renal and digital arteries.

    Science.gov (United States)

    Rosato, E; Barbano, B; Gigante, A; Cianci, R; Molinaro, I; Quarta, S; Digiulio, M A; Messineo, D; Pisarri, S; Salsano, F

    2013-01-01

    Erectile dysfunction (ED) prevalence in male systemic sclerosis (SSc) is high and its pathogenesis is unclear. The aim of the study is to assess correlation between Doppler ultrasound indices of penis and kidneys or digital arteries in male systemic sclerosis. Fourteen men with systemic sclerosis were enrolled in this study. Erectile function was investigated by the International Index of Erectile Function-5. Peak systolic velocity, end diastolic velocity, resistive index, pulsative index, and systolic/diastolic ratio were measured on the cavernous arteries at the peno-scrotal junction in the flaccid state, on the interlobar artery of both kidneys and all ten proper palmar digital arteries. Ten (71 percent) patients have an International Index of Erectile Function-5 less than 21. Reduction of penis peak systolic velocity was observed in all SSc subjects. Doppler indices of cavernous arteries correlate with the International Index of Erectile Function-5. The renal and digital arteries resistive index demonstrated a good correlation (p less than 0.0001) with International Index of Erectile Function-5. A positive correlation exists between penis and kidney arteries Doppler indices: end diastolic velocity (p less than 0.05, r=0.54), resistive index (p less than 0.0001, r=0.90), systolic/diastolic ratio (p less than 0.01, r=0.69). A positive correlation was observed between penis and digital arteries Doppler indices: peak systolic velocity (p less than 0.01, r=0.68), end diastolic velocity (p less than 0.01, r=0.75), resistive index (p less than 0.001, r=0.79), systolic/diastolic ratio (p less than 0.05, r=0.59). A correlation exists between arterial impairment of penis and renal or digital arteries.

  16. Assessment of ureterovesical jet dynamics in obstructed ureter by urinary stone with color Doppler and duplex Doppler examinations.

    Science.gov (United States)

    Jandaghi, Ali Babaei; Falahatkar, Siavash; Alizadeh, Ahmad; Kanafi, Alireza Rajabzadeh; Pourghorban, Ramin; Shekarchi, Babak; Zirak, Amin Keshavarz; Esmaeili, Samaneh

    2013-04-01

    This study was designed to evaluate ureterovesical jet dynamics in obstructed ureter and to compare it with those of contralateral unobstructed side. Forty-six patients with diagnosis of ureteral stone, based on imaging findings in computed tomography were enrolled in this study. The gray-scale ultrasound exam from both kidneys and urinary bladder was performed. Then, ureterovesical jet characteristics including ureteral jet frequency, duration and peak velocity were assessed by color Doppler and duplex Doppler studies in both obstructed and unobstructed ureters by a radiologist, 15-30 min after oral hydration with 750-1,000 mL of water. When compared with contralateral normal side, the ureterovesical jet in obstructed ureter showed less frequency (0.59 vs. 3.04 jets/min; P < 0.05), shorter duration (1.24 vs. 5.26 s; P < 0.05) and lower peak velocity (5.41 vs. 32.09 cm/s; P < 0.05). The cut-off points of 1.5 jets/min, 2.5 s and 19.5 cm/s for difference of ureteral jet frequency, duration and peak velocity between obstructed and contralateral normal ureters yielded sensitivities of 97.8, 95.6 and 100 % and specificities of 87, 87.9 and 97.8 %, respectively for diagnosis of ureteral obstruction. Given the safety of Doppler study and significant differences in flow dynamics of obstructed versus unobstructed ureters, our findings demonstrated the utility of Doppler ultrasound examination as a useful adjunct to gray-scale ultrasound by improving the accuracy of ultrasound exam in diagnosis of ureteral obstruction.

  17. Aplicação da ultrassonografia colorida doppler em programas de transferência de embriões equinos Potential use of doppler ultrasound in equine embryo transfer programs

    Directory of Open Access Journals (Sweden)

    Jair Camargo Ferreira

    2011-06-01

    Full Text Available Os programas comerciais de transferência de embriões em éguas existem por mais de três décadas e são hoje uma das biotécnias mais utilizadas na reprodução assistida de equinos. O exame ultrassonográfico nos períodos pré e pós-cobertura de doadoras de embriões, assim como a avaliação de receptoras no momento da inovulação é de vital importância para o êxito de um programa de transferência de embriões. A ultrassonografia Doppler é uma técnica não-invasiva que permite a avaliação em tempo real da hemodinâmica do trato reprodutivo de animais de grande porte. Por fornecer detalhes anatômicos e informações imediatas sobre a fisiologia do fluxo sanguíneo de tecidos e órgãos, o exame doppler permite a avaliação do potencial ovulatório de folículos e do status funcional de corpo lúteo e útero, além de ser uma técnica auxiliar para o diagnóstico de distúrbios na hemodinâmica do sistema reprodutivo. Alterações na perfusão sanguínea dos futuros folículos dominantes são detectáveis em diferentes fases de seu desenvolvimento, como na divergência folicular e no período pré-ovulatório. A partir dessas informações, é possível determinar o princípio da atividade sexual e o momento ideal para o início de tratamentos superovulatórios e indutores de ovulação, assim como o momento mais apropriado para a realização de coberturas de éguas doadoras de embriões. A avaliação através do modo-Doppler do corpo lúteo e útero de éguas receptoras é também um instrumento auxiliar para a seleção de animais com perfil sérico de progesterona e ambiente uterino adequados para a sobrevivência do embrião e manutenção da gestação. Essa técnica pode ser útil ainda ao se avaliar a interação concepto-maternal. Apesar da aplicabilidade da tecnologia doppler dentro de programas de transferência de embriões, novos estudos visando a determinar padrões de normalidade e posterior caracterização de

  18. Avaliação do ventrículo direito pelo ecocardiograma com doppler tecidual na embolia pulmonar aguda

    Directory of Open Access Journals (Sweden)

    Ana Clara Tude Rodrigues

    2013-06-01

    Full Text Available FUNDAMENTO: A avaliação da função Ventricular Direita (VD pelo ecocardiograma em pacientes com Tromboembolismo Pulmonar (TEP é complexa, frequentemente qualitativa; o Doppler tecidual tem sido utilizado para avaliação semiquantitativa dessa câmara, com algumas limitações. OBJETIVO: Avaliar a função do VD no TEP pelo ecocardiograma com Doppler tecidual, complementando com o peptídeo atrial natriurético (BNP. MÉTODOS: Foram estudados pacientes com TEP pelo ecocardiograma com Doppler tecidual e BNP até 24 horas do diagnóstico, obtendo-se as velocidades miocárdicas (s', strain, strain rate e índice de performance miocárdica do VD; disfunção do VD foi iagnosticada por hipocinesia da câmara, movimento anormal septal e relação VD/VE >1. De acordo com o BNP os pacientes foram divididos em Grupo I, BNP 50 pg/mL. RESULTADOS: De 118 pacientes, 100 (60 homens, idade = 55 ± 17 anos foram analisados; observou-se disfunção do VD em 28%, mais frequentemente no grupo II (19 vs. 9 pacientes, p < 0,001. O grupo II era mais idoso (64 ± 19 vs. 50 ± 15 anos, apresentava menor velocidade de s' (10,5 ± 3,5 vs. 13,2 ± 3,1 cm/s e maior pressão pulmonar (48 ± 11 vs. 35 ± 11 mmHg, p < 0,001 para todos. O ponto de corte de s' para disfunção do VD foi de 10,8 cm/s (especificidade = 85%, sensibilidade = 54%, com moderada correlação entre o BNP e a onda s'(r = -0,39. CONCLUSÃO: No TEP, a disfunção do VD pelo ecocardiograma se acompanha de elevação do BNP; apesar confirmar adequadamente a presença de disfunção do VD, o Doppler tecidual apresenta sensibilidade limitada para este diagnóstico.

  19. Las cosas por su nombre

    OpenAIRE

    Storani, Emilia

    2017-01-01

    El artículo propone indagar sobre los modos y diferentes formatos que se utilizan tanto en la escritura como en la lectura, para articular con las luchas por la identidad de género. La Ley de Identidad de Género ha sido un puntapié clave para pensarnos a nosotros mismos culturalmente y para pensar a los demás. Pero, ¿cómo mencionamos, escribimos y leemos las diferentes identidades? La escritura, también es un mundo transformador para quienes bregan por una sociedad más libre y sin prejuicios....

  20. Ptose palpebral causada por Paquidermoperiostose

    Directory of Open Access Journals (Sweden)

    Patricia Regina de Pinho Tavares

    2014-08-01

    Full Text Available A paquidermoperiostose é uma síndrome caracterizada por acometimento cutâneo e ósseo, e em alguns casos ocorre comprometimento palpebral leve. É uma síndrome rara, idiopática ou hereditária, com provável herança autossômica dominante de penetrância variável. Descreve-se o caso de um paciente com ptose grave por paquidermoperiostose elucidando sua fisiopatologia e conduta cirúrgica aplicada.

  1. Diverticulitis yeyunal perforada por enterolito.

    OpenAIRE

    Marenco De la Cuadra, Beatriz; Gomez-Rosado, Juan-Carlos; Capitan-Morales, Luis-Cristobal; Valdés Hernández, Javier; Reyes-lopera, N.J. De los

    2012-01-01

    La diverticulosis yeyunal es una enfermedad adquirida rara. Casi el 60-70% keeps asymptomátic or Con síntomas crónicos inespecíficos, aunque puede presentarse como un abdomen agudo. La perforación debida a enterolitos es una causa extremadamente rara do complicación, y puede producirse por la impactación de ésta contra la pared intestinal. Presentamos caso de un varón de 82 años que acude a urgencias por un dolor súbito abdominal, difuso, con irritación peritoneal, leucocitosis con neutro...

  2. Mortalidad intrahospitalaria por accidente cerebrovascular

    OpenAIRE

    Federico Rodríguez Lucci; Virginia Pujol Lereis; Sebastián Ameriso; Guillermo Povedano; María F. Díaz; Alejandro Hlavnicka; Néstor A. Wainsztein; Sebastián F. Ameriso

    2013-01-01

    La mortalidad global por accidente cerebrovascular (ACV) ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Str...

  3. Gold nanorods as a contrast agent for Doppler optical coherence tomography.

    Directory of Open Access Journals (Sweden)

    Bo Wang

    Full Text Available To investigate gold nanorods (GNRs as a contrast agent to enhance Doppler optical coherence tomography (OCT imaging of the intrascleral aqueous humor outflow.A serial dilution of GNRs was scanned with a spectral-domain OCT device (Bioptigen, Durham, NC to visualize Doppler signal. Doppler measurements using GNRs were validated using a controlled flow system. To demonstrate an application of GNR enhanced Doppler, porcine eyes were perfused at constant pressure with mock aqueous alone or 1.0×10(12 GNR/mL mixed with mock aqueous. Twelve Doppler and volumetric SD-OCT scans were obtained from the limbus in a radial fashion incremented by 30°, forming a circular scan pattern. Volumetric flow was computed by integrating flow inside non-connected vessels throughout all 12 scans around the limbus.At the GNR concentration of 0.7×10(12 GNRs/mL, Doppler signal was present through the entire depth of the testing tube without substantial attenuation. A well-defined laminar flow profile was observed for Doppler images of GNRs flowing through the glass capillary tube. The Doppler OCT measured flow profile was not statistically different from the expected flow profile based upon an autoregressive moving average model, with an error of -0.025 to 0.037 mm/s (p = 0.6435. Cross-sectional slices demonstrated the ability to view anterior chamber outflow ex-vivo using GNR-enhanced Doppler OCT. Doppler volumetric flow measurements were comparable to flow recorded by the perfusion system.GNRs created a measureable Doppler signal within otherwise silent flow fields in OCT Doppler scans. Practical application of this technique was confirmed in a constant pressure ex-vivo aqueous humor outflow model in porcine eyes.

  4. Color doppler energy (CDE) : initial ten-months experience

    International Nuclear Information System (INIS)

    Ro, Young Jin; Son, Hyun Ju; Lee, Suck Hong; Kim, Byung Soo; Han, Kook Sang; Nam, SAng Hwa; Lee, Keum Seob; Shin Se Kwon

    1996-01-01

    Color Doppler imaging(CDI) has shortcomings, including random noise, aliasing, and angle dependence. To overcome these, a method using CD US, termed power doppler or Color Doppler Energy(CDE), has recently been introduced. The purpose of this study was to show the clinical usefulness of CDE. We retrospectively analyzed the CDI and CDE of 61 cases(20 renal pseudotumors, 8 musculoskeletal inflammations, 17 epididymitis or epididymo-orchitis, 3 varicoceles, 1 normal testis, 1 hepatocellualr carcinoma, 7 renal cell carcinoma, 1 renal angiomyolipoma, and 3 splenic varices). CDI and CDE scans were obtained at the same region with constant scan plane. The color gain was increased until noise first became perceptible, and scans were always obtained in such a way that the maximum amount of vascularity was shown. Thereafter, the vascularity, vascular displacement, and the vascular relationship between CDI and CDE were compared. In 17 of 20 cases of pseudotumor in the kidney, normal vascularity was identified in CDI and CDE, but was more cleary visible in CDE. In three cases, there was no visible vascularity in CDI, but normal vascularity in CDE. In eight cases of musculoskeletal inflammation and 17 cases of epididymitis with or without orchitis, the vascularity was increased due to hyperemia, which was more prominently seen in CDE than in CDI. In three varicoceles, CDE appeared to be better in demonstrating low velocity flow. In one patient who was suspected of having acute testicular torsion, CDE was helpful in excluding this suspicion. In one case of hepatocellualr carcinoma, seven cases of renal cell carcinoma, one case of renal angiomyolipoma, and three cases of splenic varices, CDE was better than CDI in showing the vascularity, vascular relationship, and vascular displacement

  5. Evaluation of turbulence measurement techniques from a single Doppler lidar

    Directory of Open Access Journals (Sweden)

    T. A. Bonin

    2017-08-01

    Full Text Available Measurements of turbulence are essential to understand and quantify the transport and dispersal of heat, moisture, momentum, and trace gases within the planetary boundary layer (PBL. Through the years, various techniques to measure turbulence using Doppler lidar observations have been proposed. However, the accuracy of these measurements has rarely been validated against trusted in situ instrumentation. Herein, data from the eXperimental Planetary boundary layer Instrumentation Assessment (XPIA are used to verify Doppler lidar turbulence profiles through comparison with sonic anemometer measurements. For 17 days at the end of the experiment, a single scanning Doppler lidar continuously cycled through different turbulence measurement strategies: velocity–azimuth display (VAD, six-beam scans, and range–height indicators (RHIs with a vertical stare.Measurements of turbulence kinetic energy (TKE, turbulence intensity, and stress velocity from these techniques are compared with sonic anemometer measurements at six heights on a 300 m tower. The six-beam technique is found to generally measure turbulence kinetic energy and turbulence intensity the most accurately at all heights (r2  ≈  0.78, showing little bias in its observations (slope of  ≈  0. 95. Turbulence measurements from the velocity–azimuth display method tended to be biased low near the surface, as large eddies were not captured by the scan. None of the methods evaluated were able to consistently accurately measure the shear velocity (r2 =  0.15–0.17. Each of the scanning strategies assessed had its own strengths and limitations that need to be considered when selecting the method used in future experiments.

  6. Coupling Between Doppler Radar Signatures and Tornado Damage Tracks

    Science.gov (United States)

    Jedlovec, Gary J.; Molthan, Andrew L.; Carey, Lawrence; Carcione, Brian; Smith, Matthew; Schultz, Elise V.; Schultz, Christopher; Lafontaine, Frank

    2011-01-01

    On April 27, 2011, the southeastern United States was raked with several episodes of severe weather. Numerous tornadoes caused extensive damage, and tragically, the deaths of over 300 people. In Alabama alone, there were 61 confirmed tornados, 4 of them produced EF5 damage, and several were on the ground an hour or more with continuous damage tracks exceeding 80km. The use of Doppler radars covering the region provided reflectivity and velocity signatures that allowed forecasters to monitors the severe storms from beginning to end issuing hundreds of severe weather warnings throughout the day. Meteorologists from the the NWS performed extensive surveys to assess the intensity, duration, and ground track of tornadoes reported during the event. Survey activities included site visits to the affected locations, analysis of radar and satellite data, aerial surveys, and interviews with eyewitnesses. Satellite data from NASA's MODIS and ASTER instruments played a helpful role in determining the location of tornado damage paths and in the assessment. High resolution multispectral and temporal composites helped forecasters corroborate their damage assessments, determine starting and ending points for tornado touchdowns, and helped to provide forecasters with a better big-picture view of the damage region. The imagery also helped to separate damage from the April 27th tornados from severe weather that occurred earlier that month. In a post analysis of the outbreak, tornado damage path signatures observed in the NASA satellite data have been correlated to "debris ball" signatures in the NWS Doppler radars and a special ARMOR dual-polarization radar operated by the University of Alabama Huntsville during the event. The Doppler radar data indicates a circular enhanced reflectivity signal and rotational couplet in the radial velocity likely associated with the tornado that is spatially correlated with the damage tracks in the observed satellite data. An algorithm to detect and

  7. Homogenization of Doppler broadening in spin-noise spectroscopy

    Science.gov (United States)

    Petrov, M. Yu.; Ryzhov, I. I.; Smirnov, D. S.; Belyaev, L. Yu.; Potekhin, R. A.; Glazov, M. M.; Kulyasov, V. N.; Kozlov, G. G.; Aleksandrov, E. B.; Zapasskii, V. S.

    2018-03-01

    The spin-noise spectroscopy, being a nonperturbative linear optics tool, is still reputed to reveal a number of capabilities specific to nonlinear optics techniques. The effect of the Doppler broadening homogenization discovered in this work essentially widens these unique properties of spin-noise spectroscopy. We investigate spin noise of a classical system—cesium atoms vapor with admixture of buffer gas—by measuring the spin-induced Faraday rotation fluctuations in the region of D 2 line. The line, under our experimental conditions, is strongly inhomogeneously broadened due to the Doppler effect. Despite that, optical spectrum of the spin-noise power has the shape typical for the homogeneously broadened line with a dip at the line center. This fact is in stark contrast with the results of previous studies of inhomogeneous quantum dot ensembles and Doppler broadened atomic systems. In addition, the two-color spin-noise measurements have shown, in a highly spectacular way, that fluctuations of the Faraday rotation within the line are either correlated or anticorrelated depending on whether the two wavelengths lie on the same side or on different sides of the resonance. The experimental data are interpreted in the frame of the developed theoretical model which takes into account both kinetics and spin dynamics of Cs atoms. It is shown that the unexpected behavior of the Faraday rotation noise spectra and effective homogenization of the optical transition in the spin-noise measurements are related to smallness of the momentum relaxation time of the atoms as compared with their spin-relaxation time. Our findings demonstrate abilities of spin-noise spectroscopy for studying dynamic properties of inhomogeneously broadened ensembles of randomly moving spins.

  8. Colour doppler ultrasound assessment of the normal neonatal hip

    International Nuclear Information System (INIS)

    Ortiz-Neira, C.L.; Laffan, E.; Daneman, A.; Fong, K.; Roposch, A.

    2009-01-01

    To determine the morphology and hemodynamic characteristics of the arterial vessels of the proximal femur according to specific anatomic regions in asymptomatic neonates in 2 pediatric-based health care institutions. Forty-three neonates (29 female, 14 male; age range, 2 d-3 mo; median age, 3 d) were enrolled in the study. Thirty-two (37%) of 86 hips were classified as Graf type IIA joints (mean alpha angle, 56.0 o ± 2.7 o ), and 54 (63%) were classified as type I joints (mean alpha angle, 65.0 o ± 4.6 o ). Colour and spectral Doppler imaging identified vessels running along the acetabular labrum, epiphyseal vessels, and femoral neck. We showed 4 different patterns of vascularity of the hips: radial, parallel, mixed radial-parallel, and indeterminate, however, they were not related to the hip maturity (P = .3, coronal plane; P = .62, transverse plane) or to the amount of colour pixels identified in each region (P = .35). The mean number of pixels in the ligamentum teres region was significantly higher than that in other regions of interest (P =.03). Except for the acetabular labrum arteries, Doppler spectrum waveforms of proximal femur arteries presented with low resistivity. There was a tendency towards females' acetabular arteries presenting with lower peak systolic velocities than males' acetabular arteries (P =.06). Colour Doppler spectrum waveforms and intensity of vascularity in normal neonatal hips differ according to the anatomic region under evaluation. This observation deserves further investigation on its role on the physiopathogenesis of neonatal hip disorders. (author)

  9. Coherent Doppler Laser Radar: Technology Development and Applications

    Science.gov (United States)

    Kavaya, Michael J.; Arnold, James E. (Technical Monitor)

    2000-01-01

    NASA's Marshall Space Flight Center has been investigating, developing, and applying coherent Doppler laser radar technology for over 30 years. These efforts have included the first wind measurement in 1967, the first airborne flights in 1972, the first airborne wind field mapping in 1981, and the first measurement of hurricane eyewall winds in 1998. A parallel effort at MSFC since 1982 has been the study, modeling and technology development for a space-based global wind measurement system. These endeavors to date have resulted in compact, robust, eyesafe lidars at 2 micron wavelength based on solid-state laser technology; in a factor of 6 volume reduction in near diffraction limited, space-qualifiable telescopes; in sophisticated airborne scanners with full platform motion subtraction; in local oscillator lasers capable of rapid tuning of 25 GHz for removal of relative laser radar to target velocities over a 25 km/s range; in performance prediction theory and simulations that have been validated experimentally; and in extensive field campaign experience. We have also begun efforts to dramatically improve the fundamental photon efficiency of the laser radar, to demonstrate advanced lower mass laser radar telescopes and scanners; to develop laser and laser radar system alignment maintenance technologies; and to greatly improve the electrical efficiency, cooling technique, and robustness of the pulsed laser. This coherent Doppler laser radar technology is suitable for high resolution, high accuracy wind mapping; for aerosol and cloud measurement; for Differential Absorption Lidar (DIAL) measurements of atmospheric and trace gases; for hard target range and velocity measurement; and for hard target vibration spectra measurement. It is also suitable for a number of aircraft operations applications such as clear air turbulence (CAT) detection; dangerous wind shear (microburst) detection; airspeed, angle of attack, and sideslip measurement; and fuel savings through

  10. Analysis of Doppler effect measurement in FCA cores using JENDL-3.2 library

    International Nuclear Information System (INIS)

    Okajima, Shigeaki

    1996-01-01

    For the evaluation of the calculation accuracy of the 238 U Doppler effect using JENDL-3.2 library, the previously measured Doppler reactivity worths in the FCA were systematically analyzed. In the analysis the Doppler reactivity worth was calculated by a first order perturbation theory. The calculated results were compared with those using JENDL-3.1 library. The JENDL-3.2 calculation in MOX fuel mock-up cores agrees well with the experimental values within the experimental error. In U-235/Pu fuel cores, the JENDL-3.2 calculation gives 12-15% larger Doppler reactivity worths than the JENDL-3.1 calculation. (author)

  11. Doppler ultrasonography of the lower extremity arteries: anatomy and scanning guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ji Young [Dept. of Radiology, Ewha Womans University School of Medicine, Seoul (Korea, Republic of)

    2017-04-15

    Doppler ultrasonography of the lower extremity arteries is a valuable technique, although it is less frequently indicated for peripheral arterial disease than for deep vein thrombosis or varicose veins. Ultrasonography can diagnose stenosis through the direct visualization of plaques and through the analysis of the Doppler waveforms in stenotic and poststenotic arteries. To perform Doppler ultrasonography of the lower extremity arteries, the operator should be familiar with the arterial anatomy of the lower extremities, basic scanning techniques, and the parameters used in color and pulsed-wave Doppler ultrasonography.

  12. Dispersed single-phase-step Michelson interferometer for Doppler imaging using sunlight.

    Science.gov (United States)

    Wan, Xiaoke; Ge, Jian

    2012-09-15

    A Michelson interferometer is dispersed with a fiber array-fed spectrograph, providing 59 Doppler sensing channels using sunlight in the 510-570 nm wavelength region. The interferometer operates at a single-phase-step mode, which is particularly advantageous in multiplexing and data processing compared to the phase-stepping mode of other interferometer spectrometer instruments. Spectral templates are prepared using a standard solar spectrum and simulated interferometer modulations, such that the correlation function with a measured 1D spectrum determines the Doppler shift. Doppler imaging of a rotating cylinder is demonstrated. The average Doppler sensitivity is ~12 m/s, with some channels reaching ~5 m/s.

  13. Doppler color flow mapping of peripheral vessels: Comparison of angiodynography with conventional duplex US

    International Nuclear Information System (INIS)

    Merritt, C.R.B.; Bluth, E.I.; Sullivan, M.A.

    1986-01-01

    A new Doppler color flow imager was compared to duplex US in the evaluation of carotid and peripheral vessels in 50 patients. A 7.5-MHz transducer permitted simultaneous high-resolution real-time imaging of Doppler flow and tissue. The system was found to have excellent image quality and Doppler sensitivity. Flow characteristics and velocity measurements obtained with this system correlated well with those obtained using the duplex scanner and were obtained more quickly than with the conventional system, allowing more complete assessment of flow characteristics. Color Doppler flow imaging appears to be an extremely promising method for the rapid and effective evaluation of peripheral vascular flow

  14. Doppler ultrasonography of the lower extremity arteries: anatomy and scanning guidelines

    Directory of Open Access Journals (Sweden)

    Ji Young Hwang

    2017-04-01

    Full Text Available Doppler ultrasonography of the lower extremity arteries is a valuable technique, although it is less frequently indicated for peripheral arterial disease than for deep vein thrombosis or varicose veins. Ultrasonography can diagnose stenosis through the direct visualization of plaques and through the analysis of the Doppler waveforms in stenotic and poststenotic arteries. To perform Doppler ultrasonography of the lower extremity arteries, the operator should be familiar with the arterial anatomy of the lower extremities, basic scanning techniques, and the parameters used in color and pulsed-wave Doppler ultrasonography.

  15. Augmented Reality Based Doppler Lidar Data Visualization: Promises and Challenges

    OpenAIRE

    Cherukuru N. W.; Calhoun R.

    2016-01-01

    Augmented reality (AR) is a technology in which the enables the user to view virtual content as if it existed in real world. We are exploring the possibility of using this technology to view radial velocities or processed wind vectors from a Doppler wind lidar, thus giving the user an ability to see the wind in a literal sense. This approach could find possible applications in aviation safety, atmospheric data visualization as well as in weather education and public outreach. As a proof of...

  16. Transcranial Doppler series. Part I: Understanding neurovascular anatomy.

    Science.gov (United States)

    Nicoletto, Heather A; Burkman, Marilyn H

    2008-12-01

    Transcranial Doppler (TCD) is an ultrasound study that evaluates the blood flow in the brain and is considered by many to be the most difficult vascular study to perform. The circle of Willis is the group of vessels that are insonated with TCD. Knowledge of the arteries that comprise the circle of Willis, the origins of these vessels, and their vessel segments can make the test easier to perform. The technologist performing the TCD must also be aware that the circle of Willis is not complete in approximately 50% of all cases. Knowledge of the various anomalies will help a technologist understand why they may not be able to insonate a vessel.

  17. Approximation of the Doppler broadening function by Frobenius method

    International Nuclear Information System (INIS)

    Palma, Daniel A.P.; Martinez, Aquilino S.; Silva, Fernando C.

    2005-01-01

    An analytical approximation of the Doppler broadening function ψ(x,ξ) is proposed. This approximation is based on the solution of the differential equation for ψ(x,ξ) using the methods of Frobenius and the parameters variation. The analytical form derived for ψ(x,ξ) in terms of elementary functions is very simple and precise. It can be useful for applications related to the treatment of nuclear resonances mainly for the calculations of multigroup parameters and self-protection factors of the resonances, being the last used to correct microscopic cross-sections measurements by the activation technique. (author)

  18. The derivation of the Doppler broadening function using Frobenius method

    International Nuclear Information System (INIS)

    Palma, Daniel A.P.; Martinez, Aquilino S.; Silva, Fernando C.

    2006-01-01

    An analytical approximation of the Doppler broadening function ψ(ξ,x) is proposed. This approximation is based on the solution of the differential equation for ψ(ξ,x) using the methods of Frobenius and parameters variation. The analytical form derived for ψ(ξ,x) in terms of elementary functions is very simple and precise. It can be useful for applications related to the treatment of nuclear resonances, mainly for calculations of multigroup parameters and resonances self-protection factors, the latter being used to correct microscopic cross section measurements by the activation technique. (author)

  19. Synchronous ultrasonic Doppler imaging of magnetic microparticles in biological tissues

    Energy Technology Data Exchange (ETDEWEB)

    Pyshnyi, Michael Ph. [Institute of Biochemical Physics, Russian Academy of Sciences, Kosygin St. 4, Moscow 119991 (Russian Federation); Kuznetsov, Oleg A. [Institute of Biochemical Physics, Russian Academy of Sciences, Kosygin St. 4, Moscow 119991 (Russian Federation)], E-mail: kuznetsov_oa@yahoo.com; Pyshnaya, Svetlana V.; Nechitailo, Galina S.; Kuznetsov, Anatoly A. [Institute of Biochemical Physics, Russian Academy of Sciences, Kosygin St. 4, Moscow 119991 (Russian Federation)

    2009-05-15

    We considered applicability of acoustic imaging technology for the detection of magnetic microparticles and nanoparticles inside soft biological tissues. Such particles are widely used for magnetically targeted drug delivery and magnetic hyperthermia. We developed a new method of ultrasonic synchronous tissue Doppler imaging with magnetic modulation for in vitro and in vivo detection and visualization of magnetic ultradisperse objects in soft tissues. Prototype hardware with appropriate software was produced and the method was successfully tested on magnetic microparticles injected into an excised pig liver.

  20. Synchronous ultrasonic Doppler imaging of magnetic microparticles in biological tissues

    International Nuclear Information System (INIS)

    Pyshnyi, Michael Ph.; Kuznetsov, Oleg A.; Pyshnaya, Svetlana V.; Nechitailo, Galina S.; Kuznetsov, Anatoly A.

    2009-01-01

    We considered applicability of acoustic imaging technology for the detection of magnetic microparticles and nanoparticles inside soft biological tissues. Such particles are widely used for magnetically targeted drug delivery and magnetic hyperthermia. We developed a new method of ultrasonic synchronous tissue Doppler imaging with magnetic modulation for in vitro and in vivo detection and visualization of magnetic ultradisperse objects in soft tissues. Prototype hardware with appropriate software was produced and the method was successfully tested on magnetic microparticles injected into an excised pig liver.

  1. Wind climatology observed over Kalpakkam using Doppler sodar

    International Nuclear Information System (INIS)

    Narayana Rao, D.; Krishna Reddy, K.; Vijaya Kumar, T.R.; Kishore, P.

    1996-01-01

    Acoustic remote sensing of the prevailing winds in the boundary layer finds an important application in studying the problems related to air pollution meteorology. Analysis of the seasonal variation of vertical and horizontal wind speed with altitude is made using the Doppler sodar data collected at an atomic research centre, Kalpakkam. A pictorial representation of horizontal wind flow for each season is given in the form of wind roses at three lower levels of probing, namely 100, 300 and 500 m. Such analysis would prove to be a basic reference material for taking necessary meaningful emergency measures in similar climatic regions. (author). 18 refs., 10 figs

  2. Laser doppler anemometry in single- and two-phase flows

    International Nuclear Information System (INIS)

    Durst, F.

    1976-01-01

    The present report gives an introduction into laser-Doppler anemometry and tries to explain the basic physical principles of this measuring technique. Moire fringe patterns are used in order to visually model LDA-signals and to explain the basic difference in optical systems. It is pointed out that LDA measurements in highly turbulent flows and in two-phase flows should be attempted with direction sensitive instruments only. Some of the optical systems developed by the author and his collaborators are introduced and their functioning in measurements is demonstrated. These measurements embrace investigations in a number of single-phase flows including flames. (orig.) [de

  3. Using microwave Doppler radar in automated manufacturing applications

    Science.gov (United States)

    Smith, Gregory C.

    Since the beginning of the Industrial Revolution, manufacturers worldwide have used automation to improve productivity, gain market share, and meet growing or changing consumer demand for manufactured products. To stimulate further industrial productivity, manufacturers need more advanced automation technologies: "smart" part handling systems, automated assembly machines, CNC machine tools, and industrial robots that use new sensor technologies, advanced control systems, and intelligent decision-making algorithms to "see," "hear," "feel," and "think" at the levels needed to handle complex manufacturing tasks without human intervention. The investigator's dissertation offers three methods that could help make "smart" CNC machine tools and industrial robots possible: (1) A method for detecting acoustic emission using a microwave Doppler radar detector, (2) A method for detecting tool wear on a CNC lathe using a Doppler radar detector, and (3) An online non-contact method for detecting industrial robot position errors using a microwave Doppler radar motion detector. The dissertation studies indicate that microwave Doppler radar could be quite useful in automated manufacturing applications. In particular, the methods developed may help solve two difficult problems that hinder further progress in automating manufacturing processes: (1) Automating metal-cutting operations on CNC machine tools by providing a reliable non-contact method for detecting tool wear, and (2) Fully automating robotic manufacturing tasks by providing a reliable low-cost non-contact method for detecting on-line position errors. In addition, the studies offer a general non-contact method for detecting acoustic emission that may be useful in many other manufacturing and non-manufacturing areas, as well (e.g., monitoring and nondestructively testing structures, materials, manufacturing processes, and devices). By advancing the state of the art in manufacturing automation, the studies may help

  4. Microembolus Detection by Transcranial Doppler Sonography: Review of the Literature

    Directory of Open Access Journals (Sweden)

    Vlasta Vuković-Cvetković

    2012-01-01

    Full Text Available Transcranial Doppler can detect microembolic signals which are characterized by unidirectional high intensity increase, short duration, random occurrence, and a “whistling” sound. Microembolic signals have been detected in a number of clinical settings: carotid artery stenosis, aortic arch plaques, atrial fibrillation, myocardial infarction, prosthetic heart valves, patent foramen ovale, valvular stenosis, during invasive procedures (angiography, percutaneous transluminal angioplasty, surgery (carotid, cardiopulmonary bypass, orthopedic, and in certain systemic diseases. Microembolic signals are frequent in large artery disease, less commonly detected in cardioembolic stroke, and infrequent in lacunar stroke. This article provides an overview about the current state of technical and clinical aspects of microembolus detection.

  5. DESAJUSTE EDUCATIVO POR REGIONES EN COLOMBIA: ¿COMPETENCIA POR SALARIOS O POR PUESTOS DE TRABAJO?

    Directory of Open Access Journals (Sweden)

    Maribel Castillo Caicedo

    2007-06-01

    Full Text Available Este trabajo aporta una perspectiva del fenómeno de la sobreeducación, entendida como un desajuste por exceso, entre el nivel educativo alcanzado por el individuo y el exigido por el puesto de trabajo en el cual se desempeña; esto se debe a que existe una demanda laboral estrecha de puestos de trabajo para personas calificadas en Colombia. Se analizan las contribuciones empíricas existentes y el debate sobre las mismas; se examinan las teorías que permiten explicar la existencia de un desajuste educativo y se realiza una revisión de la literatura internacional y nacional sobre el tema. Adicionalmente, se plantean una serie de hipótesis para desarrollar un esquema que permita determinar el comportamiento del individuo en el fenómeno de la sobreeducación.

  6. Consanguinidad por isonimia en Salta

    Directory of Open Access Journals (Sweden)

    Albeza, María V.

    2007-01-01

    Full Text Available Se estimó el coeficiente de parentesco por isonimia para localidades de la Puna, Valle Calchaquí y Valle de Lerma, a fin de evaluar diferentes factores evolutivos que podrían estar afectando la composición genética de la población. A partir de los apellidos de las parejas consignadas en fuentes primarias de información, se estimó la isonimia conyugal o marital, el coeficiente total Ft y sus componentes Fr (inbreeding azaroso y Fn (inbreeding no azaroso. De las localidades estudiadas, en la Puna se ha detectado sólo una pareja isónima en una de ellas, en el Valle Calchaquí, tres y ninguna en el Valle de Lerma. Tanto en el Valle Calchaquí como en el de Lerma, se han estimado valores negativos de Ft, y en la Puna se registran los valores más elevados. En las localidades estudiadas no se cumple el supuesto de transmisión patrilineal de apellidos por lo que los valores de Fr y por ende de Ft podrían estar subestimados. Es por ello que sería necesario contar con información desde otras vertientes metodológicas para corroborar, complementar y manejar cuidadosamente el análisis de los datos y las conclusiones que se obtienen.

  7. Celulitis por citomegalovirus Cytomegalovirus cellulitis

    Directory of Open Access Journals (Sweden)

    A. Ruiz Lascano

    2002-12-01

    Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.Cutaneous lesions in CMV infection are rare, often a late manifestation of systemic infection, and usually herald a fatal course. A 70 year-old woman received a kidney transplantation one month before consulting and immunosuppressive therapy that included cyclosporine A and methylprednisone. She complained of fever, local pain in her right leg, and an erythematous and swelling plaque. She was treated with intravenous antibiotics without improvement. A skin biopsy was performed and the tissue obtained was sent for bacterial and fungal cultures as well as for histological examination. Cultures were negative. The biopsy showed CMV cytopathic changes. Immunoperoxidase staining was positive for CMV and polymerase chain reaction (PCR testing revealed CMV DNA. She was treated with ganciclovir with resolution of the lesion. CMV cellulitis is a rare cutaneous manifestation

  8. Corruption of radio metric Doppler due to solar plasma dynamics: S/X dual-frequency Doppler calibration for these effects

    Science.gov (United States)

    Winn, F. B.; Reinbold, S. R.; Yip, K. W.; Koch, R. E.; Lubeley, A.

    1975-01-01

    Doppler data from Mariner 6, 7, 9, and 10 and Pioneer 10 and 11 were discussed and the rms noise level for various sun-earth-probe angles were shown. The noise levels of both S- and X-band Doppler data for sun-earth-probe angles smaller than 20 deg were observed to be orders of magnitude greater than nominal. Such solar plasma-related Doppler degradation reduced the Mariner 10-Mercury 11 encounter navigation accuracy by nearly a factor of 10. Furthermore, this degradation was shown to be indirectly related to plasma dynamics and not a direct measure of the dynamics.

  9. Importância da ecogenicidade da tireóide no diagnóstico da tireoidite crônica auto-imune Value of thyroid echogenicity in the diagnosis of chronic autoimmune thyroiditis

    Directory of Open Access Journals (Sweden)

    Danilo Bianchini Höfling

    2008-12-01

    Full Text Available A tireoidite crônica auto-imune é, atualmente, a principal causa de hipotireoidismo e seu diagnóstico baseia-se nas manifestações clínico-laboratoriais. O marcador laboratorial mais importante é a presença de anticorpos antitireoglobulina e antiperoxidase, sendo este último o teste mais sensível. A biópsia aspirativa apresenta alta sensibilidade e especificidade, porém, é um método invasivo e, por isso, reservado para quando há presença de nódulo ou bócio de crescimento rápido. A cintilografia é desnecessária para o diagnóstico, já que apresenta baixa sensibilidade e especificidade. A ultra-sonografia, tanto ao modo B como ao dúplex-Doppler colorido, evoluiu de forma muito rápida e tornou-se um método simples, não-invasivo, reprodutível e com alta sensibilidade para o diagnóstico da tireoidite crônica auto-imune. Ao modo B, a ecogenicidade é um parâmetro de extrema importância, já que, além de apresentar alta correlação com o quadro citopatológico, também apresenta alta sensibilidade para o diagnóstico da tireoidite crônica auto-imune. Embora este parâmetro não seja específico da tireoidite crônica auto-imune, pois também pode estar presente na doença de Graves, na tireoidite pós-parto e na tireoidite subaguda, tais desordens podem ser facilmente diferenciadas tanto pelo quadro clínico-laboratorial quanto pelo dúplex-Doppler colorido. Assim, este artigo tem o objetivo de revisar a importância do estudo da ecogenicidade no diagnóstico da tireoidite crônica auto-imune.Chronic autoimmune thyroiditis is currently considered as the main cause for hypothyroidism and its diagnosis is based on clinical manifestations and laboratory tests results. The most significant laboratory marker for this disease is the presence of anti-thyroperoxidase and anti-thyroglobulin antibodies, the latter being the most sensitive one. Aspiration biopsy shows high sensitivity and specificity but, considering the

  10. Approximation of the Doppler broadening function by Frobenius method; Aproximacao da funcao de alargamento doppler atraves do metodo de Frobenius

    Energy Technology Data Exchange (ETDEWEB)

    Palma, Daniel A.P. [Centro Federal de Educacao Tecnologica de Quimica de Nilopolis/RJ (CEFET), RJ (Brazil)]. E-mail: dpalma@cefeteq.br; Martinez, Aquilino S.; Silva, Fernando C. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear]. E-mail: aquilino@lmp.ufrj.br; fernando@lmn.con.ufrj.br

    2005-07-01

    An analytical approximation of the Doppler broadening function {psi}(x,{xi}) is proposed. This approximation is based on the solution of the differential equation for {psi}(x,{xi}) using the methods of Frobenius and the parameters variation. The analytical form derived for {psi}(x,{xi}) in terms of elementary functions is very simple and precise. It can be useful for applications related to the treatment of nuclear resonances mainly for the calculations of multigroup parameters and self-protection factors of the resonances, being the last used to correct microscopic cross-sections measurements by the activation technique. (author)

  11. Mucosal blood flow measurements using laser Doppler perfusion monitoring

    Institute of Scientific and Technical Information of China (English)

    Dag Arne Lihaug Hoff; Hans Gregersen; Jan Gunnar Hatlebakk

    2009-01-01

    Perfusion of individual tissues is a basic physiological process that is necessary to sustain oxygenation and nutrition at a cellular level. Ischemia, or the insufficiency of perfusion, is a common mechanism for tissue death or degeneration, and at a lower threshold, a mechanism for the generation of sensory signalling including pain. It is of considerable interest to study perfusion of peripheral abdominal tissues in a variety of circumstances. Microvascular disease of the abdominal organs has been implicated in the pathogenesis of a variety of disorders, including peptic ulcer disease, inflammatory bowel disease and chest pain. The basic principle of laser Doppler perfusion monitoring (LDPM) is to analyze changes in the spectrum of light reflected from tissues as a response to a beam of monochromatic laser light emitted. It reflects the total local microcirculatory blood perfusion, including perfusion in capillaries, arterioles, venules and shunts. During the last 20-25 years, numerous studies have been performed in different parts of the gastrointestinal (GI) tract using LDPM. In recent years we have developed a multi-modal catheter device which includes a laser Doppler probe, with the intent primarily to investigate patients suffering from functional chest pain of presumed oesophageal origin. Preliminary studies show the feasibility of incorporating LDPM into such catheters for performing physiological studies in the GI tract. LDPM has emerged as a research and clinical tool in preference to other methods; but, it is important to be aware of its limitations and account for them when reporting results.

  12. Modeling of Doppler frequency shift in multipath radio channels

    Directory of Open Access Journals (Sweden)

    Penzin M.S.

    2016-06-01

    Full Text Available We discuss the modeling of propagation of a quasi-monochromatic radio signal, represented by a coherent pulse sequence, in a non-stationary multipath radio channel. In such a channel, signal propagation results in the observed frequency shift for each ray (Doppler effect. The modeling is based on the assumption that during propagation of a single pulse a channel can be considered stationary. A phase variation in the channel transfer function is shown to cause the observed frequency shift in the received signal. Thus, instead of measuring the Doppler frequency shift, we can measure the rate of variation in the mean phase of one pulse relative to another. The modeling is carried out within the framework of the method of normal waves. The method enables us to model the dynamics of the electromagnetic field at a given point with the required accuracy. The modeling reveals that a local change in ionospheric conditions more severely affects the rays whose reflection region is in the area where the changes occur.

  13. Mesospheric gravity wave momentum flux estimation using hybrid Doppler interferometry

    Directory of Open Access Journals (Sweden)

    A. J. Spargo

    2017-06-01

    Full Text Available Mesospheric gravity wave (GW momentum flux estimates using data from multibeam Buckland Park MF radar (34.6° S, 138.5° E experiments (conducted from July 1997 to June 1998 are presented. On transmission, five Doppler beams were symmetrically steered about the zenith (one zenith beam and four off-zenith beams in the cardinal directions. The received beams were analysed with hybrid Doppler interferometry (HDI (Holdsworth and Reid, 1998, principally to determine the radial velocities of the effective scattering centres illuminated by the radar. The methodology of Thorsen et al. (1997, later re-introduced by Hocking (2005 and since extensively applied to meteor radar returns, was used to estimate components of Reynolds stress due to propagating GWs and/or turbulence in the radar resolution volume. Physically reasonable momentum flux estimates are derived from the Reynolds stress components, which are also verified using a simple radar model incorporating GW-induced wind perturbations. On the basis of these results, we recommend the intercomparison of momentum flux estimates between co-located meteor radars and vertical-beam interferometric MF radars. It is envisaged that such intercomparisons will assist with the clarification of recent concerns (e.g. Vincent et al., 2010 of the accuracy of the meteor radar technique.

  14. Hypercholesterolemia and Myocardial function evaluated via Tissue Doppler Imaging

    Directory of Open Access Journals (Sweden)

    Kotaru Pavan

    2009-11-01

    Full Text Available Abstract Objective To establish a link between hypercholesterolemia and myocardial dysfunction. Background Heart failure is a complex disease involving changes in systolic and diastolic function. Newer echocardiographic imaging modalities may be able to detect discreet changes in myocardial function associated with hypercholesterolemia. Therefore we sought to establish a link between hypercholesterolemia and myocardial dysfunction with tissue Doppler imaging (TDI. Methods Twenty-seven rabbits were studied: 7 were fed normal chow (group 1 and 20 a high cholesterol diet (10 with ezetimibe, 1 mg/kg/day; group 2 and 10 without, group 3. Echocardiographic images were obtained under general anesthesia. Serum cholesterol levels were obtained at baseline, 3 and 6 months and myocardial cholesterol levels measured following euthanasia. Results Doppler measurements, including E/A, E'/A' and S' were significantly lower in group 3 compared to both groups 1 and 2 but no significant differences were noted in chamber sizes or ejection fraction among the groups. Average serum cholesterol was higher in group 3 compared to groups 1 and 2 respectively (495 ± 305 mg/dl vs. 114 ± 95 mg/dl and 87 ± 37 mg/dl; p 2 = 0.17 p = 0.04, r2 = 0.37 p = 0.001 and r2 = 0.24 p = 0.01. Conclusion Cholesterol load in the serum and myocardium was significantly associated with decreased systolic and diastolic function by TDI. Moreover, lipid lowering was protective.

  15. A phased array antenna for Doppler reflectometry in ASDEX upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, Stefan; Lechte, Carsten; Kasparek, Walter [IGVP, Universitaet Stuttgart, D-70569 Stuttgart (Germany); Hennequin, Pascale [Laboratoire de Physique des Plasmas, CNRS, Ecole Polytech., F-91128 Palaiseau (France); Conway, Garrard; Happel, Tim [Max-Planck-Institut fuer Plasmaphysik, D-85748 Garching (Germany); Collaboration: ASDEX Upgrade Team

    2016-07-01

    In a toroidal plasma, Doppler reflectometry (DR) allows investigating electron density fluctuations with finite k {sub perpendicular} {sub to}. The injected microwave beam's frequency determines the radial position of the probed region, its tilt angle selects the wavenumber satisfying the Bragg condition for backscattering. The rotation velocity can be calculated from the Doppler shift of the backscattered signal's frequency. By varying the injected frequency, radial profiles can be reconstructed. Varying the tilt angle resolves the k {sub perpendicular} {sub to} -spectrum of the fluctuations. For DR, a pair of phased array antennas (PAAs) has been designed, built, and installed in the ASDEX Upgrade tokamak. Beam steering is done by slightly changing the injected frequency, thus, the PAAs do not need any movable parts or electronics inside the vacuum vessel. From 75 to 105 GHz, the PAAs feature 13 frequency bands, each with an angular scan range of -20 to +20 {sup circle}. So, for each angle, there are 13 radial positions to be probed. The results from PAA characterisation, commissioning, and first DR measurements are presented.

  16. Mesospheric gravity wave momentum flux estimation using hybrid Doppler interferometry

    Science.gov (United States)

    Spargo, Andrew J.; Reid, Iain M.; MacKinnon, Andrew D.; Holdsworth, David A.

    2017-06-01

    Mesospheric gravity wave (GW) momentum flux estimates using data from multibeam Buckland Park MF radar (34.6° S, 138.5° E) experiments (conducted from July 1997 to June 1998) are presented. On transmission, five Doppler beams were symmetrically steered about the zenith (one zenith beam and four off-zenith beams in the cardinal directions). The received beams were analysed with hybrid Doppler interferometry (HDI) (Holdsworth and Reid, 1998), principally to determine the radial velocities of the effective scattering centres illuminated by the radar. The methodology of Thorsen et al. (1997), later re-introduced by Hocking (2005) and since extensively applied to meteor radar returns, was used to estimate components of Reynolds stress due to propagating GWs and/or turbulence in the radar resolution volume. Physically reasonable momentum flux estimates are derived from the Reynolds stress components, which are also verified using a simple radar model incorporating GW-induced wind perturbations. On the basis of these results, we recommend the intercomparison of momentum flux estimates between co-located meteor radars and vertical-beam interferometric MF radars. It is envisaged that such intercomparisons will assist with the clarification of recent concerns (e.g. Vincent et al., 2010) of the accuracy of the meteor radar technique.

  17. Numerical study of glare spot phase Doppler anemometry

    Science.gov (United States)

    Hespel, C.; Ren, K. F.; Gréhan, G.; Onofri, F.

    2008-03-01

    The phase Doppler anemometry has (PDA) been developed to measure simultaneously the velocity and the size of droplets. When the concentration of particles is high, tightly focused beams must be used, as in the dual burst PDA. The latter permits an access to the refractive index of the particle, but the effect of wave front curvature of the incident beams becomes evident. In this paper, we introduce a glare spot phase Doppler anemometry which uses two large beams. The images of the particle formed by the reflected and refracted light, known as glare spots, are separated in space. When a particle passes through the probe volume, the two parts in a signal obtained by a detector in forward direction are then separated in time. If two detectors are used the phase differences and the intensity ratios between two signals, the distance between the reflected and refracted spots can be obtained. These measured values provide information about the particle diameter and its refractive index, as well as its two velocity components. This paper is devoted to the numerical study of such a configuration with two theoretical models: geometrical optics and rigorous electromagnetism solution.

  18. Color Doppler Ultrasonographic Features of Hashimoto's Thyroiditis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo Hyuk; Kim, Mie Young; Rho, Eun Jin; Yi, Jeong Geun; Han, Chun Hwan [Kangnam General Hospital Public Corporation, Seoul (Korea, Republic of); Hwang, Hee Yong [Choong Ang Gil Hospital, Incheon (Korea, Republic of)

    1995-06-15

    Color Doppler ultrasonographic(US) features of 28 patients with Hashimato's thyroiditis were evaluated with regard to echo and color-flow patterns. Correlation of color-flow pattern with thyroid function was performed. All 28 patients showed varying degrees of diffuse enlargement of the thyroid gland and a heterogeneous echo pattern.Color-flow pattern of increased blood flow. Low to moderate, focally increased blood flow was seen in 26 patients(92.8%). Of these 26 patients, 24 patients showed subclinical hypothyroidism or euthyroidism. Two patients who showed hyperthyroidism showed several pieces of focally increased color flow, Which was noted during both systole and diastole. Diffuse, multifocal color-flow throughout thyroid gland was seen in two patients with Hashimato's thyroiditis: one with clinical hypothyroidism and the other with subclinical hypothyroidism. Even though Hashimoto's thyroiditis showed variable color-flow patterns, we believe that heterogenous parenchymal echopattern with low or moderately increased flow is a rather characteristic feature of Hashimoto's thyroiditis, and we suggest that color Doppler US provides additional information for evaluation of Hashimoto's thyroiditis

  19. Adaptation of Dunn Solar Telescope for Jovian Doppler spectro imaging

    Science.gov (United States)

    Underwood, Thomas A.; Voelz, David; Schmider, François-Xavier; Jackiewicz, Jason; Dejonghe, Julien; Bresson, Yves; Hull, Robert; Goncalves, Ivan; Gualme, Patrick; Morand, Frédéric; Preis, Olivier

    2017-09-01

    This paper describes instrumentation used to adapt the Dunn Solar Telescope (DST) located on Sacramento Peak in Sunspot, NM for observations using the Doppler Spectro Imager (DSI). The DSI is based on a Mach-Zehnder interferometer and measures the Doppler shift of solar lines allowing for the study of atmospheric dynamics of giant planets and the detection of their acoustic oscillations. The instrumentation is being designed and built through a collaborative effort between a French team from the Observatoire de la Cote d'Azur (OCA) that designed the DSI and a US team at New Mexico State University (NMSU). There are four major components that couple the DSI to the DST: a guider/tracker, fast steering mirror (FSM), pupil stabilizer and transfer optics. The guider/tracker processes digital video to centroid-track the planet and outputs voltages to the DST's heliostat controls. The FSM removes wavefront tip/tilt components primarily due to turbulence and the pupil stabilizer removes any slow pupil "wander" introduced by the telescope's heliostat/turret arrangement. The light received at a science port of the DST is sent through the correction and stabilization components and into the DSI. The FSM and transfer optics designs are being provided by the OCA team and serve much the same functions as they do for other telescopes at which DSI observations have been conducted. The pupil stabilization and guider are new and are required to address characteristics of the DST.

  20. THD Doppler procedure for hemorrhoids: the surgical technique.

    Science.gov (United States)

    Ratto, C

    2014-03-01

    Transanal hemorrhoidal dearterialization (THD) is an effective treatment for hemorrhoidal disease. The ligation of hemorrhoidal arteries (called "dearterialization") can provide a significant reduction of the arterial overflow to the hemorrhoidal piles. Plication of the redundant rectal mucosa/submucosa (called "mucopexy") can provide a repositioning of prolapsing tissue to the anatomical site. In this paper, the surgical technique and perioperative patient management are illustrated. Following adequate clinical assessment, patients undergo THD under general or spinal anesthesia, in either the lithotomy or the prone position. In all patients, distal Doppler-guided dearterialization is performed, providing the selective ligation of hemorrhoidal arteries identified by Doppler. In patients with hemorrhoidal/muco-hemorrhoidal prolapse, the mucopexy is performed with a continuous suture including the redundant and prolapsing mucosa and submucosa. The description of the surgical procedure is complemented by an accompanying video (see supplementary material). In long-term follow-up, there is resolution of symptoms in the vast majority of patients. The most common complication is transient tenesmus, which sometimes can result in rectal discomfort or pain. Rectal bleeding occurs in a very limited number of patients. Neither fecal incontinence nor chronic pain should occur. Anorectal physiology parameters should be unaltered, and anal sphincters should not be injured by following this procedure. When accurately performed and for the correct indications, THD is a safe procedure and one of the most effective treatments for hemorrhoidal disease.

  1. Digital storage and analysis of color Doppler echocardiograms

    Science.gov (United States)

    Chandra, S.; Thomas, J. D.

    1997-01-01

    Color Doppler flow mapping has played an important role in clinical echocardiography. Most of the clinical work, however, has been primarily qualitative. Although qualitative information is very valuable, there is considerable quantitative information stored within the velocity map that has not been extensively exploited so far. Recently, many researchers have shown interest in using the encoded velocities to address the clinical problems such as quantification of valvular regurgitation, calculation of cardiac output, and characterization of ventricular filling. In this article, we review some basic physics and engineering aspects of color Doppler echocardiography, as well as drawbacks of trying to retrieve velocities from video tape data. Digital storage, which plays a critical role in performing quantitative analysis, is discussed in some detail with special attention to velocity encoding in DICOM 3.0 (medical image storage standard) and the use of digital compression. Lossy compression can considerably reduce file size with minimal loss of information (mostly redundant); this is critical for digital storage because of the enormous amount of data generated (a 10 minute study could require 18 Gigabytes of storage capacity). Lossy JPEG compression and its impact on quantitative analysis has been studied, showing that images compressed at 27:1 using the JPEG algorithm compares favorably with directly digitized video images, the current goldstandard. Some potential applications of these velocities in analyzing the proximal convergence zones, mitral inflow, and some areas of future development are also discussed in the article.

  2. Particle sizing experiments with the laser Doppler velocimeter: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Giel, T.V. Jr.; Son, J.Y.

    1988-06-01

    Measurement techniques for in-situ simultaneous measurements of particle size distributions and particle velocities using the dual beam laser Doppler velocimeter (LV) were analytically and experimentally investigated. This investigation examined the different signal characteristics of the LV for determination of particle size and particle velocity, simultaneously. The different size related signal components were evaluated not only singularly but also as simultaneous measurements to determine which characteristic, or combination of characteristics, provided the best measure of particle size. The evaluation concentrated on the 0.5 to 5 ..mu..m particle size range, in which the LV light scattering characteristics are complex often non-monotonic functions of the particle size as well as functions of index of refraction, the laser light wavelength, laser intensity and polarization, and the location and response characteristics of the detector. Different components of the LV signal were considered, but analysis concentrated on Doppler phase, visibility and scatter-intensity because they show the greatest promise. These signals characteristics were initially defined analytically for numerous optical configurations over the 0.5 to 5 ..mu..m diameter range with 0.1 ..mu..m segmentation, for refractive index values from 1.0 to 3.0 with absorptive (imaginary) components varied form 0 to 1.0. Collector orientation and effective f/No., as well as fringe spacing, beam polarization and wavelength, were varied in this analytical evaluation. 18 refs., 42 figs., 5 tabs.

  3. Diagnosis of brain death by transcranial Doppler sonography.

    Science.gov (United States)

    Bode, H; Sauer, M; Pringsheim, W

    1988-12-01

    The blood flow velocities in the basal cerebral arteries can be recorded at any age by transcranial Doppler sonography. We examined nine children with either initial or developing clinical signs of brain death. Soon after successful resuscitation increased diastolic flow velocities indicated a probable decrease in cerebrovascular resistance; this was of no particular prognostic importance. As soon as there was a clinical deterioration, there was a reduction in flow velocities with retrograde flow during early diastole, probably due to an increase in cerebrovascular resistance; this indicated a doubtful prognosis. In eight of the nine children with clinical signs of brain death a typical reverberating flow pattern was found, which was characterised by a counterbalancing short forward flow in systole and a short retrograde flow in early diastole. This indicated arrest of cerebral blood flow. One newborn showed normal systolic and end diastolic flow velocities in the basal cerebral arteries for two days despite clinical and electroencephalographic signs of brain death. Shunting of blood through the circle of Willis without effective cerebral perfusion may explain this phenomenon. No patient had the typical reverberating flow pattern without being clinically brain dead. Transcranial Doppler sonography is a reliable technique, which can be used at the bedside for the confirmation or the exclusion of brain death in children in addition to the clinical examination.

  4. Detection of Doppler Microembolic Signals Using High Order Statistics

    Directory of Open Access Journals (Sweden)

    Maroun Geryes

    2016-01-01

    Full Text Available Robust detection of the smallest circulating cerebral microemboli is an efficient way of preventing strokes, which is second cause of mortality worldwide. Transcranial Doppler ultrasound is widely considered the most convenient system for the detection of microemboli. The most common standard detection is achieved through the Doppler energy signal and depends on an empirically set constant threshold. On the other hand, in the past few years, higher order statistics have been an extensive field of research as they represent descriptive statistics that can be used to detect signal outliers. In this study, we propose new types of microembolic detectors based on the windowed calculation of the third moment skewness and fourth moment kurtosis of the energy signal. During energy embolus-free periods the distribution of the energy is not altered and the skewness and kurtosis signals do not exhibit any peak values. In the presence of emboli, the energy distribution is distorted and the skewness and kurtosis signals exhibit peaks, corresponding to the latter emboli. Applied on real signals, the detection of microemboli through the skewness and kurtosis signals outperformed the detection through standard methods. The sensitivities and specificities reached 78% and 91% and 80% and 90% for the skewness and kurtosis detectors, respectively.

  5. Comparison of the Diagnostic Performance of Power Doppler Ultrasound and a New Microvascular Doppler Ultrasound Technique (AngioPLUS) for Differentiating Benign and Malignant Breast Masses.

    Science.gov (United States)

    Jung, Hae Kyoung; Park, Ah Young; Ko, Kyung Hee; Koh, Jieun

    2018-03-12

    This study was performed to compare the diagnostic performance of power Doppler ultrasound (US) and a new microvascular Doppler US technique (AngioPLUS; SuperSonic Imagine, Aix-en-Provence, France) for differentiating benign and malignant breast masses. Power Doppler US and AngioPLUS findings were available in 124 breast masses with confirmed pathologic results (benign, 80 [64.5%]; malignant, 44 [35.5%]). The diagnostic performance of each tool was calculated to distinguish benign from malignant masses using a receiver operating characteristic curve analysis and compared. The area under the curve showed that AngioPLUS was superior to power Doppler US in differentiating benign from malignant breast masses, but the difference was not statistically significant. © 2018 by the American Institute of Ultrasound in Medicine.

  6. Tratamento de gestação cervical viável com aplicação intra-amniótica de metotrexato: relato de um caso Treatment of a viable cervical pregnancy with a single-intraamniotic methotrexate injection: a case report

    Directory of Open Access Journals (Sweden)

    José Juvenal Linhares

    2006-10-01

    Full Text Available Gestação cervical é uma condição rara, em que ocorre implantação do ovo no canal cervical distendendo-o à medida que cresce. Corresponde a menos de 1% de todas as gestações ectópicas. A hemorragia indolor é sua característica clínica habitual e ao exame físico visualiza-se um colo hipertrófico e vascularizado, com tecido saindo pelo orifício externo do colo. Ultra-sonografia pode ser usada para complementar o diagnóstico, mostrando a presença do saco gestacional. Relatamos um caso de tratamento bem sucedido de gestação cervical viável de sete semanas. Morte fetal foi conseguida com uma injeção intra-amniótica única de metotrexato (25 mg guiada por ultra-sonografia transvaginal. Metotrexato sistêmico em dose única intramuscular (50 mg/m² foi associado. O tratamento conservador da gestação cervical com metotrexato foi efetivo e seguro.Cervical pregnancy is a rare condition in which the egg is implanted in the cervical canal causing it to distend as the egg grows. Cervical pregnancy constitutes less than 1% of all ectopic pregnancies. Painless hemorrhage is a habitual clinical characteristic and on physical examination a very vascularized hypertrophic cervix is observed with a tissue surpassing the external orifice. Ultrasonography may be used as a complementary diagnostic tool to show directly the presence of a gestational sac. A successful management of a viable seven-week gestation cervical pregnancy is reported herein. Feticide was performed with a single intraamniotic methotrexate injection (25 mg guided by transvaginal ultrasonography. Systemic methotrexate in a single dose intramuscular (50 mg/m² was associated. The conservative management of cervical ectopic pregnancy with methotrexate was effective and safe.

  7. PARÂMETROS REPRODUTIVOS DE MATRIZES SUÍNAS INSEMINADAS COM SÊMEN DILUÍDO EM ÁGUA DE COCO APÓS MONITORAMENTO ULTRA-SONOGRÁFICO TRANSCUTÂNEO

    Directory of Open Access Journals (Sweden)

    Pierre Castro Soares

    2006-10-01

    Full Text Available Com o objetivo de avaliar o efeito de diluidores de sêmen (MERK III, BTS e água de coco acrescida de citrato de sódio a 5% sobre parâmetros reprodutivos de matrizes suínas, utilizou-se sêmen diluído nas concentrações de 4x109 e 8x109 espermatozóides/100ml na inseminação artificial de 173 fêmeas púberes e 184 adultas, com prévio monitoramento ultra-sonográfico do estro e ovulação. O diagnóstico de gestação também foi realizado por ultra-sonografia transcutânea. Os dados revelaram altas percentagens (89,5% a 95,6% de prenhes das matrizes suínas púberes e adultas, sem variação significativa entre os tipos de diluidores utilizados. Sugere-se, portanto, que a água de coco in natura pode ser utilizada na diluição de sêmen suíno, significando uma alternativa de baixo custo, e que monitoramento ultra-sonográfico transcutâneo constitui um método auxiliar no diagnóstico de estro, ovulação e prenhez. PALAVRAS-CHAVE: Suíno, sêmen, água de coco, MERK III, BTS, ultra-sonografia.

  8. Esporotricosis diagnosticada por el laboratorio

    Directory of Open Access Journals (Sweden)

    Nelly Ordóñez

    1989-06-01

    Full Text Available De 1976 a 1989 se han diagnosticado 40 casos de esporotricosis en el laboratorio de Micología del Instituto Nacional de Salud. La enfermedad se presentó en pacientes entre 4 y 52 años y tuvo predilección por el sexo masculino: 35 de 40 (87,5%; las formas clínicas más frecuentes fueron la cutánea fija, 18 de 40 (45%, y la linfocutánea, 17 de 40 (42,5%, con localización mayor en miembros superiores, 18 de 40 (45%. El diagnóstico se estableció por el aislamiento del Sporothrix schenckii en 35 de 38 pacientes (92%; los otros dos pacientes se diagnosticaron empleando otras técnicas: inmunofluorescencia directa, intradermorreacción y aglutinación en tubo.

  9. Miasis cutanea por cordylobia anthropophaga

    Directory of Open Access Journals (Sweden)

    Alkorta Gurrutxaga Miriam

    2001-01-01

    Full Text Available El incremento progresivo en el número de personas que viajan a países tropicales ha hecho que las enfermedades importadas adquieran una relevancia cada vez mayor. Las miasis (o infestaciones por larvas de moscas cutáneas se encuentran entre este tipo de enfermedades siendo especialmente frecuentes en países tropicales. A propósito de la observación de un caso de miasis cutánea masiva por Cordylobia antropophaga, que ocurrió en una mujer de 34 años de edad al volver de un viaje a Senegal, se ha efectuado una revisión de los casos de miasis cutáneas forunculoides importadas publicados en España, así como de la biología, patología, tratamiento y prevención de la miasis humana por Cordylobia anthropophaga. El caso referido, se caracterizó por la infestación con un número inusualmente elevado de larvas, no sospechándose su etiología hasta la fase final de la enfermedad. La emergencia continuada de larvas (se recogieron 91 generó en la paciente un estado de ansiedad importante. Finalmente, la eliminación de las larvas provocó una rápida mejoría de la paciente. Aunque los casos de miasis cutánea no tienen la gravedad de otras enfermedades importadas, su conocimiento es necesario desde el punto de vista preventivo, diagnóstico y terapeútico. Es importante proceder a la identificación morfológica de las larvas diferenciándolas de otro tipo de miasis con implicaciones terapéuticas diferentes.

  10. Correlation between clinical examination, mammography and ultrasonography with histopathological exam in the determination of tumor size in breast cancer; Correlacao entre o exame clinico, a mamografia e a ultra-sonografia com o exame anatomopatologico na determinacao do tamanho tumoral no cancer de mama

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Fernanda Monteiro de Paula; Rezende, Cezar Alencar de Lima [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Medicina. Dept. de Ginecologia e Obstetricia]. E-mail: fersiqueira75@yahoo.com.br; Barra, Alexandre de Almeida [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Hospital das Clinicas. Servico de Diagnostico por Imagem

    2008-07-01

    Purpose: to evaluate which method is the best to determine pre-surgically the size of breast cancer: clinical examination, mammography or ultrasonography, using as a reference the anatomopathological exam. Methods: this study has included 184 patients with palpable-or-not breast lesions, detected by mammography and ultrasonography, that were submitted to surgical resection of the tumor, with histopathological diagnosis of breast cancer. The same examiner evaluated clinically the largest tumoral diameter, through clinical examination, mammography and ultrasonography, and the measurements obtained by each method were correlated with the maximum diameter obtained by the anatomopathological exam. The comparative analysis has been done by Pearson's correlation coefficient (r). Results: Pearson's correlation coefficient between the anatomopathological and the clinical exams was 0.8; between the anatomopathological exam and the mammography, 0.7; and between anatomopathological exam and ultrasonography 0.7 (p<0.05). Pearson's correlation coefficients among the methods evaluated were also calculated and r=0.7 was obtained between clinical exam and mammography, r=0.8 between clinical examination and ultrasonography, and r=0.8 between mammography and ultrasonography (p<0.05). Conclusions: clinical examination, mammography and ultrasonography have presented high correlation with the anatomopathological measures, besides high correlations among themselves, what seems to show that they may be used as equivalent methods in the pre-surgical evaluation of the breast tumoral size. Nevertheless, due to specific limitations of each method, clinical examination, mammography and ultrasonography should be seen as complementary to each other, in order to obtain a more accurate measurement of the breast cancer tumor.(author)

  11. Role of Doppler US and MRI in diagnosis of placenta accreta ...

    African Journals Online (AJOL)

    The aim of this work is to evaluate the role of Doppler US and MRI in the diagnosis of placenta accreta. Patients and methods: During period between 2012 to 2013, 120 pregnant patients with previous cesarean section were investigated by ultrasound and Doppler and then in suspected cases MRI was obtained (10 cases).

  12. Temporal Doppler Effect and Future Orientation: Adaptive Function and Moderating Conditions.

    Science.gov (United States)

    Gan, Yiqun; Miao, Miao; Zheng, Lei; Liu, Haihua

    2017-06-01

    The objectives of this study were to examine whether the temporal Doppler effect exists in different time intervals and whether certain individual and environmental factors act as moderators of the effect. Using hierarchical linear modeling, we examined the existence of the temporal Doppler effect and the moderating effect of future orientation among 139 university students (Study 1), and then the moderating conditions of the temporal Doppler effect using two independent samples of 143 and 147 university students (Studies 2 and 3). Results indicated that the temporal Doppler effect existed in all of our studies, and that future orientation moderated the temporal Doppler effect. Further, time interval perception mediated the relationship between future orientation and the motivation to cope at long time intervals. Finally, positive affect was found to enhance the temporal Doppler effect, whereas control deprivation did not influence the effect. The temporal Doppler effect is moderated by the personality trait of future orientation and by the situational variable of experimentally manipulated positive affect. We have identified personality and environmental processes that could enhance the temporal Doppler effect, which could be valuable in cases where attention to a future task is necessary. © 2016 Wiley Periodicals, Inc.

  13. Musculoskeletal colour/power Doppler in sports medicine: image parameters, artefacts, image interpretation and therapy

    DEFF Research Database (Denmark)

    Boesen, M I; Boesen, Mikael; Kønig, Merete Juhl

    2010-01-01

    This review article discusses the aspects of sports medicine where musculoskeletal Doppler ultrasound has valuable contribution in diagnosis and/or treatment of some of the typical musculoskeletal sports injuries. Also, conditions where the Doppler ultrasound has no value are discussed. Some...

  14. Musculoskeletal colour/power Doppler in sports medicine: image parameters, artefacts, image interpretation and therapy

    DEFF Research Database (Denmark)

    Boesen, M I; Boesen, Mikael; Kønig, Merete Juhl

    2011-01-01

    This review article discusses the aspects of sports medicine where musculoskeletal Doppler ultrasound has valuable contribution in diagnosis and/or treatment of some of the typical musculoskeletal sports injuries. Also, conditions where the Doppler ultrasound has no value are discussed. Some...

  15. Screening for aortoiliac lesions by visual interpretation of the common femoral Doppler waveform

    DEFF Research Database (Denmark)

    Eiberg, J P; Jensen, F; Grønvall Rasmussen, J B

    2001-01-01

    to study the accuracy of simple visual interpretation of the common femoral artery Doppler waveform for screening the aorto-iliac segment for significant occlusive disease.......to study the accuracy of simple visual interpretation of the common femoral artery Doppler waveform for screening the aorto-iliac segment for significant occlusive disease....

  16. An analytical model for the description of the full-polarimetric sea surface Doppler signature

    NARCIS (Netherlands)

    Fois, F.; Hoogeboom, P.; Le Chevalier, F.; Stoffelen, A.

    2015-01-01

    This paper describes an analytical model of the full-polarimetric sea surface scattering and Doppler signature. The model combines the small-slope-approximation theory (at the second order) with a weak nonlinear sea surface representation. Such a model is used to examine the variation of the Doppler

  17. Effect of preload alternations on a new Doppler echocardiographic index of combined systolic and diastolic performance

    DEFF Research Database (Denmark)

    Møller, J E; Poulsen, S H; Egstrup, K

    1999-01-01

    The objective of the study was to assess the effect of preload alternations on a nongeometric Doppler index of combined systolic and diastolic myocardial performance (MPI). Doppler echocardiography was performed during Valsalva maneuver, passive leg lifting, and after sublingual administration of...

  18. The use ofDoppler velocitnetry ofthe utnbilical artery before 24 ...

    African Journals Online (AJOL)

    growth retardation with umbilical artery Doppler ultrasonography. BM] 1989; 298: 631-635. 12. Schulman H, Winter D, Farmakides G, er al. Pregnancy surveil- lance with Doppler velocimerry of the uterine and umbilical arter- ies. Am] Obstet Gyneco11989; 160: 192-196. 13. Hanrerry KP, Primrose MH, Neilson JP, Whittle MJ.

  19. Current Perspectives in Hyperbaric Physiology, Ultrasonic Doppler Bubble Detection, and Mass Spectrometry,

    Science.gov (United States)

    1979-12-28

    Doppler sound made by a bubble passing through the inson- ified volume blood vessel resembles a very sharp truncated whistle , chirp or click depending...the Doppler ultrasound , suffered the "slings and arrows of outrageous criticism" to borrow and beat a phrase. It is not appropriate to go into this

  20. Explanation of the Inverse Doppler Effect Observed in Nonlinear Transmission Lines

    International Nuclear Information System (INIS)

    Kozyrev, Alexander B.; Weide, Daniel W. van der

    2005-01-01

    The theory of the inverse Doppler effect recently observed in magnetic nonlinear transmission lines is developed. We explain the crucial role of the backward spatial harmonic in the occurrence of an inverse Doppler effect and draw analogies of the magnetic nonlinear transmission line to the backward wave oscillator

  1. Radar Micro-Doppler Feature Extraction Using the Singular Value Decomposition

    NARCIS (Netherlands)

    Wit, J.J.M. de; Harmanny, R.I.A.; Molchanov, P.

    2014-01-01

    Abstract—The micro-Doppler spectrogram depends on parts of a target moving and rotating in addition to the main body motion (e.g., spinning rotor blades) and is thus characteristic for the type of target. In this study, the micro-Doppler spectrogram is exploited to distinguish between birds and

  2. Can duplex Doppler ultrasound replace computerized tomography in staging patients with renal cell carcinoma?

    NARCIS (Netherlands)

    Bos, SD; Mensink, HJA

    The purpose of this study was to evaluate the accuracy and reliability of duplex Doppler ultrasound (US) and computerized tomography (CT) in staging patients with renal cell carcinoma (RCC). Sixty-six patients were evaluated pre-operatively with duplex Doppler ultrasound and CT. The results were

  3. Discrimination between pleural thickening and minimal pleural effusion using color Doppler chest ultrasonography

    Directory of Open Access Journals (Sweden)

    Ali A. Hasan

    2013-07-01

    Conclusions: Application of color Doppler examination increases the accuracy of real time chest ultrasound to discriminate pleural thickening from minimal pleural effusion and hence color Doppler examination proved to be a useful diagnostic tool to real-time gray-scale ultrasound for diagnosis of minimal pleural effusion.

  4. Structure of a swirl-stabilized spray flame by imaging, laser Doppler velocimetry, and phase Doppler anemometry

    Science.gov (United States)

    Edwards, C. F.; Rudoff, R. C.

    1991-01-01

    Data are presented which describe the mean structure of a steady, swirl-stabilized, kerosene spray flame in the near-injector region of a research furnace. The data presented include ensemble-averaged results of schlieren, luminosity, and extinction imaging, measurement of the gas phase velocity field by laser Doppler velocimetry, and characterization of the condensed phase velocity by phase Doppler anemometry. The results of these studies define six key regions in the flame: the dense spray region; the rich, two-phase, fuel jet; the main air jet; the internal product recirculation zone; the external product recirculation zone; and the gaseous diffusion flame zone. The first five of these regions form a conical mixing layer which prepares the air and fuel for combustion. The air and fuel jets comprise the central portion of this mixing layer and are bounded on either side by the hot product gases of the internal and external recirculation zones. Entrainment of these product gases into the air/fuel streams provides the energy required to evaporate the fuel spray and initiate combustion. Intermittency of the internal recirculation and spray jet flows accounts for unexpected behavior observed in the aerodynamics of the two phases. The data reported herein are part of the database being accumulated on this spray flame for the purpose of detailed comparison with numerical modeling.

  5. Comparação dos métodos de imagem no diagnóstico dos tumores renais e calcificações nestas neoplasias Comparison of imaging methods for diagnosis of renal tumors and their calcifications

    Directory of Open Access Journals (Sweden)

    Sergio Marrone Ribeiro

    2004-12-01

    Full Text Available OBJETIVO: Tentar estabelecer uma metodologia no diagnóstico e conduta dos pacientes com massas renais sólidas e complexas, comparando os custos e benefícios dos diferentes métodos de diagnóstico por imagem. Procuramos avançar no diagnóstico diferencial entre lesões benignas e malignas, particularmente através da investigação das calcificações tumorais. MÉTODOS: Realizamos um estudo prospectivo em 31 pacientes portadores de massas renais sólidas ou complexas, todos eles submetidos à ultra-sonografia abdominal (US, ultra-sonografia doppler da massa renal (US Dop, tomografia computadorizada (TC e ressonância magnética (RM. RESULTADOS: Encontramos 28 pacientes com massas malignas e três com massas benignas. Entre os 28 pacientes com lesões malignas, 17 mostraram calcificações pela TC; 16 deles calcificações do tipo central e um calcificação do tipo curvilinear periférica pura (casca de ovo. A urografia excretora (UGE mostrou uma taxa de detecção para calcificações significantemente menor que a US e a TC. Massas benignas e malignas apareceram como descrito na literatura, com o US, TC e RM mostrando alta sensibilidade e especificidade no diagnóstico dos tumores renais. A exceção foi na US Dop, onde nós obtivemos menor sensibilidade para a caracterização de fluxo tumoral maligno. CONCLUSÕES: Foi surpreendente verificar que a TC revelou calcificações centrais em 51,6% dos pacientes desta série, todas elas em lesões malignas, quando a literatura refere uma freqüência de calcificações entre 8% e 22% dos carcinomas de células renais, em estudos utilizando radiografias simples do abdômen e UGE. Este achado é de grande importância quando consideramos que estas calcificações ocorrem particularmente em neoplasias malignas. Como resultado da comparação dos diferentes métodos de diagnóstico por imagem, nós propomos uma metodologia para adequada investigação dos tumores renais.BACKGROUND: To establish the

  6. Direct measurement of Lorentz transformation with Doppler effects

    Science.gov (United States)

    Chen, Shao-Guang

    For space science and astronomy the fundamentality of one-way velocity of light (OWVL) is selfevident. The measurement of OWVL (distance/interval) and the clock synchronization with light-signal transfer make a logical circulation. This means that OWVL could not be directly measured but only come indirectly from astronomical method (Romer's Io eclipse and Bradley's sidereal aberration), furthermore, the light-year by definitional OWVL and the trigonometry distance with AU are also un-measurable. For to solve this problem two methods of clock synchronization were proposed: The direct method is that at one end of dual-speed transmissionline with single clock measure the arriving-time difference of longitudinal wave and transverse wave or ordinary light and extraordinary light, again to calculate the collective sending-time of two wave with Yang's /shear elastic-modulus ratio (E/k) or extraordinary/ordinary light refractive-index ratio (ne/no), which work as one earthquake-station with single clock measures first-shake time and the distance to epicenter; The indirect method is that the one-way wavelength l is measured by dual-counters Ca and Cb and computer's real-time operation of reading difference (Nb - Na) of two counters, the frequency f is also simultaneously measured, then l f is just OWVL. Therefore, with classical Newtonian mechanics and ether wave optics, OWVL can be measured in the Galileo coordinate system with an isotropic length unit (1889 international meter definition). Without any hypotheses special relativity can entirely establish on the metrical results. When a certain wavelength l is defined as length unit, foregoing measurement of one-way wavelength l will become as the measurement of rod's length. Let a rigidity-rod connecting Ca and Cb moves relative to lamp-house with velocity v, rod's length L = (Nb - Na) l will change follow v by known Doppler effect, i.e., L(q) =L0 (1+ (v/c) cos q), where L0 is the proper length when v= 0, v• r = v cos q

  7. Hiperecogenicidade dos vasos talâmicos no recém-nascido prematuro Hyperechogenicity of thalamic vessels in preterm newborn infants

    Directory of Open Access Journals (Sweden)

    Natália Paczko

    2002-09-01

    Full Text Available Objetivo: o presente estudo procura avaliar as possíveis patologias que se manifestam associadas à hiperecogenicidade dos vasos talâmicos na ultra-sonografia cerebral, e observar a freqüência com que ocorrem. Métodos: a amostra foi constituída de 206 recém-nascidos prematuros, nascidos no Hospital de Clínicas de Porto Alegre, no período de julho de 1998 a maio de 1999. Todos realizaram a ultra-sonografia cerebral na primeira semana de vida. Foram incluídos no estudo aqueles prematuros que necessitaram de internação hospitalar, e que tiveram o termo de consentimento informado assinado por um dos responsáveis. Foram excluídos aqueles cuja ultra-sonografia cerebral evidenciava sangramento cerebral e/ou malformações congênitas associadas, e os que evoluíram para óbito antes da realização do exame. Resultados: a ultra-sonografia cerebral levou à identificação de 65 recém-nascidos prematuros com hiperecogenicidade dos vasos talâmicos e de 141 recém-nascidos prematuros sem. Conclusão: a forma de apresentação do tipo pélvica ao nascimento, a maior idade gestacional, o maior peso do recém-nascido ao nascimento e a classificação grande para a idade gestacional foram fatores de risco para a ocorrência de hiperecogenicidade dos vasos talâmicos, enquanto a presença de hipertensão materna durante o período de gestação tendeu a ser fator de proteção. Os recém-nascidos que apresentaram crises convulsivas durante o período de internação hospitalar tiveram risco 3,2 vezes maior de ter hiperecogenicidade dos vasos talâmicos, quando comparados aos que não apresentaram crises convulsivas.Objective: the aim of this study is to evaluate possible pathologies associated with hyperechogenicity of thalamic vessels (HETV, which are found on brain ultrasounds (BUS, as well as to observe the frequency of their occurrence. Methods: the sample was composed of 206 preterm newborn infants at Hospital de Clíncas de Porto Alegre

  8. Ultrasound and Doppler examination capabilities in adult portal hypertension type definition

    Directory of Open Access Journals (Sweden)

    N. V. Tumanskaya

    2015-08-01

    Full Text Available Early portal hypertension type diagnostics is an ultimate factor concerning kind and tactics of treatment. Aim. To objectify ultrasound examination capabilities, portal hemodynamics were studied in 97 patients using impulse and color doppler. Methods and results. It was ascertained that impulse and color doppler examination allows to visualize portal vein and its branches’ structural abnormalities, define subhepatic and intrahepatic types of portal hypertension, find thrombosis and characterize its stages. In cirrhosis patients with portal hypertension, homogenous doppler signal was received from the portal vessels lumen, while signs of intraluminar pathology were seen in the case of thrombosis of portal vein. Conclusion. This means that ultrasound examination of portal vein and its branches with impulse and color doppler is informative, non invasive method, which helps to define stages of portal hypertension. Doppler ultrasonography doesn’t have negative effect of ionizing radiation and can be used for the repeated research in the dynamics of disease.

  9. Collapse and revival of the Doppler-Rabi oscillations of a moving atom in a cavity

    International Nuclear Information System (INIS)

    Kozlovskii, A. V.

    2008-01-01

    Collapse and revival of the Doppler-Rabi oscillations of a two-level atom moving in a cavity electromagnetic field are analyzed. The coupled atom-field dynamics are predicted accurately by numerical calculation and approximately by using the stationary phase approximation combined with the Poisson summation formula. The collapse and revival patterns are shown to be qualitatively different in the cases of moving atom and atom at rest. In particular, quantum revivals of Doppler-Rabi oscillations occur with a period determined by the Doppler shift of the atomic transition frequency. This regime of Doppler-Rabi oscillations requires that the Rabi frequency and the Doppler shift satisfy the condition Ω R D . Under the inverse relation, the collapse- revival phenomenon generally does not occur. It is shown that even a small amount of atom-cavity detuning eliminates collapse-revival behavior. The analysis is performed for both coherent and thermal cavity fields

  10. Micro-Doppler Ambiguity Resolution Based on Short-Time Compressed Sensing

    Directory of Open Access Journals (Sweden)

    Jing-bo Zhuang

    2015-01-01

    Full Text Available When using a long range radar (LRR to track a target with micromotion, the micro-Doppler embodied in the radar echoes may suffer from ambiguity problem. In this paper, we propose a novel method based on compressed sensing (CS to solve micro-Doppler ambiguity. According to the RIP requirement, a sparse probing pulse train with its transmitting time random is designed. After matched filtering, the slow-time echo signals of the micromotion target can be viewed as randomly sparse sampling of Doppler spectrum. Select several successive pulses to form a short-time window and the CS sensing matrix can be built according to the time stamps of these pulses. Then performing Orthogonal Matching Pursuit (OMP, the unambiguous micro-Doppler spectrum can be obtained. The proposed algorithm is verified using the echo signals generated according to the theoretical model and the signals with micro-Doppler signature produced using the commercial electromagnetic simulation software FEKO.

  11. Korea-China Joint R and D on Doppler Lidar Technology

    International Nuclear Information System (INIS)

    Cha, Hyung Ki; Kim, D. H.; Kwon, S. O.; Yang, K. H.; Song, I. K.

    2009-03-01

    Doppler lidar technology is to monitor atmospheric wind velocity by measuring the light scattering signals between a laser and aerosol particles or molecules existing in the atmosphere. When the particles (or molecules) in the atmosphere are moving by wind force, the frequency of backscattering light is shifted by doppler effect, so that the wind velocity profile can be obtained by measurement of the shifted frequencies. When the laser radiation is scanned in four different direction, three dimensional wind profiles are obtained. The Anhui Institute of Optics and Fine Mechanics under the China Academy of Sciences has developed and operated the doppler lidar system for long time. In this project we want to developed a new technologies adopted to the chinese doppler system and to test the updated In the process of collaboration between China and Korea research teams, we want to learn the state-of-art technology involved in the doppler lidar system

  12. GPM GROUND VALIDATION DUAL-FREQUENCY DUAL-POLARIZED DOPPLER RADAR (D3R) IFLOODS V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Dual-frequency Dual-polarized Doppler Radar (D3R) IFloodS data set contain radar reflectivity and doppler velocity measurements. The D3R...

  13. Abdome agudo por obstrução por ileobiliar

    Directory of Open Access Journals (Sweden)

    Márcia Cristina de Alencastro

    Full Text Available OBJETIVO: descrever a experiência na abordagem dos doentes com abdome agudo por obstrução por IB, desde o diagnóstico até o tratamento definitivo. MÉTODOS: estudo retrospectivo incluindo todos os casos de IB tratados em um período de 23 anos. De acordo com a abordagem cirúrgica realizada, os pacientes foram divididos em dois grupos (1 enterolitotomia com colecistectomia no segundo momento; e (2 enterolitotomia, colecistectomia e abordagem da fístula. RESULTADOS: Doze pacientes foram incluídos, sendo 11 mulheres (91,6%, com média de idade de 72,2 anos. Todos os pacientes apresentavam doenças associadas, principalmente hipertensão arterial sistêmica (75%. Dois pacientes não apresentavam sintomas significativos de obstrução intestinal. O diagnóstico de IB foi realizado em seis pacientes (50% antes da laparotomia. O grupo 1 foi constituído de oito pacientes e o grupo 2 de quatro, e a morbidade foi, respectivamente, 33,3% e 8,3%. A mortalidade foi 16,6% (um paciente de cada grupo. CONCLUSÃO: O manejo do IB deve ser individualizado. O tratamento da obstrução mediante remoção do cálculo biliar por enterotomia proximal é a escolha inicial para o tratamento do IB. A colecistectomia e a correção da fístula bilioentérica podem ser realizadas juntamente com a remoção do cálculo, no entanto, em pacientes com comorbidades significativas, esses procedimentos devem ser realizados posteriormente.

  14. A demonstrator for an incoherent Doppler wind lidar receiver

    Science.gov (United States)

    Fabre, F.; Marini, A.; Sidler, Thomas C.; Morancais, Didier; Fongy, G.; Vidal, Ph.

    2018-04-01

    The knowledge of wind fields for a global terrestrial coverage and accurate altitude sampling is one of the main keys for improvement of meteorological predictions and general understanding of atmosphere behaviour. The best way to recover this information is remote sensing from space using low Earth orbit satellites. The measurement principle is to analyse the Doppler shift of the flux emitted by the space instrument and backscattered by the atmosphere. One of the most promising principle for Doppler shift measurement is the direct detection which does not need local oscillators. what significantly simplifies the design of such a space-borne receiver. ESA-ESTEC initiated at early 95' a programme called "lncoherent Doppler Wind Lidar (IDWL) technologies" for the study and bread-boarding phase. MMS won this contract proposing an original concept based on the use of a Fizeau high resolution interferometer working in the UV band. coupled with an intensified CCD. This concept is patented by MMS, as well as the special CCD timing sequence that will be depicted below. The programme begun by a study of the space-borne instrument in order to identify main constraints and define the receiver as could be for a flight model. A detailed performance model was established and parametric analysis allowed to optimise the concept in order to reach required performances. This study phase finally provided the definition of a bread-board for expected performances demonstration. Moreover, the Laser Signal Simulator (LSS) which is used to simulate the Lidar echo in term of amplitude as well as frequency modulation was defined at this step. The performances of this test support equipment are of main importance for the validation of the demonstrator design and performances. The second part of the study aimed at defining the derailed design of the demonstrator and associated test support equipment as well as initiating preliminary validation experiments on most critical technologies, like

  15. Aplicação clínica da ultrassonografia craniana com Doppler em neonatos prematuros de muito baixo peso Clinical application of transcranial Doppler ultrasonography in premature, very-low-birth-weight neonates

    Directory of Open Access Journals (Sweden)

    Marta Lúcia Gabriel

    2010-08-01

    Full Text Available OBJETIVO: Analisar o valor do diagnóstico precoce de alterações hemodinâmicas em hemorragias e eventos hipóxico-isquêmicos pela avaliação de imagens e mensuração do índice de resistência por meio da ultrassonografia craniana com Doppler em neonatos prematuros de muito baixo peso. MATERIAIS E MÉTODOS: Cinquenta neonatos prematuros de muito baixo peso foram submetidos a ultrassonografia craniana com Doppler com a técnica transfontanela anterior e transtemporal sequenciais. RESULTADOS: Foram detectadas alterações cerebrais em 32% dos prematuros, sendo 22% com hemorragia intracraniana, 8% com leucomalácia periventricular e 2% com toxoplasmose. Dentre os 34 casos (68%, do total de neonatos, nos quais não foram detectadas lesões cerebrais pela ultrassonografia craniana, 18 (53% apresentaram alterações no índice de resistência. O índice de resistência variou conforme a época do exame. CONCLUSÃO: Existe correlação entre a presença de alterações na hemodinâmica cerebral e subsequente desenvolvimento de hemorragias e lesões hipóxico-isquêmicas, pela mensuração do índice de resistência. Alterações do índice de resistência, embora não preditoras de morte, estão relacionadas com a gravidade do quadro clínico em neonatos prematuros de muito baixo peso.OBJECTIVE: The present study was aimed at analyzing the value of the early diagnosis of hemodynamic changes in hemorrhages and hypoxic-ischemic events in premature, very-low-birth-weight neonates through the evaluation of images and resistance index measurement by means of transcranial Doppler ultrasonography. MATERIALS AND METHODS: Fifty premature, very-low-birth-weight neonates were submitted to transcranial Doppler ultrasonography with sequential transfontanellar and transtemporal techniques. RESULTS: Cerebral abnormalities were detected in 32% of the neonates (22% with intracranial hemorrhage, 8% with periventricular leukomalacia, and 2% with toxoplasmosis

  16. Transesophageal color Doppler evaluation of obstructive lesions using the new "Quasar" technology.

    Science.gov (United States)

    Fan, P; Nanda, N C; Gatewood, R P; Cape, E G; Yoganathan, A P

    1995-01-01

    Due to the unavoidable problem of aliasing, color flow signals from high blood flow velocities cannot be measured directly by conventional color Doppler. A new technology termed Quantitative Un-Aliased Speed Algorithm Recognition (Quasar) has been developed to overcome this limitation. Employing this technology, we used transesophageal color Doppler echocardiography to investigate whether the velocities detected by the Quasar would correlate with those obtained by continuous-wave Doppler both in vitro and in vivo. In the in vitro study, a 5.0 MHz transesophageal transducer of a Kontron Sigma 44 color Doppler flow system was used. Fourteen different peak velocities calculated and recorded by color Doppler-guided continuous-wave Doppler were randomly selected. In the clinical study, intraoperative transesophageal echocardiography was performed using the same transducer 18 adults (13 aortic valve stenosis, 2 aortic and 2 mitral stenosis, 2 hypertrophic obstructive cardiomyopathy and 1 mitral valve stenosis). Following each continuous-wave Doppler measurement, the Quasar was activated, and a small Quasar marker was placed in the brightest area of the color flow jet to obtain the maximum mean velocity readout. The maximum mean velocities measured by Quasar closely correlated with maximum peak velocities obtained by color flow guided continuous-wave Doppler in both in vitro (0.53 to 1.65 m/s, r = 0.99) and in vivo studies (1.50 to 6.01 m/s, r = 0.97). We conclude that the new Quasar technology can accurately measure high blood flow velocities during transesophageal color Doppler echocardiography. This technique has the potential of obviating the need for continuous-wave Doppler.

  17. Transthoracic Doppler echocardiography to predict optimal tube pulsing window for coronary artery CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Gang, E-mail: cjr.sungang@vip.163.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Li, Min, E-mail: limin22000@yahoo.com.cn [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Jiang, Xiang-sen, E-mail: jiangxiangsen123@126.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Li, Li, E-mail: leely1976@yahoo.com.cn [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Peng, Zhao-hui, E-mail: zhaohuipeng_R@163.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Mu, Nan-nan, E-mail: munannan22000@sohu.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China)

    2012-09-15

    Rationale and objective: To evaluate the feasibility of transthoracic Doppler echocardiography to determine the optimal pulsing windows for CT coronary angiography to narrow the pulsing windows further, especially in higher heart rate. Materials and methods: Doppler was performed on 135 patients before CT scanning. For Doppler, the intervals with minimal motion were evaluated during both systole and diastole integrating electrocardiogram (ECG) intervals. For CT scanning, the retrospective ECG-gating was applied and the optimal reconstruction intervals were determined. The accuracy of Doppler analysis to predict the optimal reconstruction intervals was tested. The predicted length of pulsing windows was compared between Doppler analysis and traditional prospective ECG-gating protocol (heart rate ≦ 65 bpm, 60–76%; 66–79 bpm, 30–77%; ≧80 bpm, 31–47%). Results: According to Doppler analysis, the mean length of intervals with minimal motion in systole was 106.4 ± 39.2 ms and 125.2 ± 92.0 ms in diastole. When the intervals with minimal motion during diastole > 90 ms, the optimal reconstruction intervals were located at diastole; otherwise, at systole (P < 0.001). The optimal reconstruction intervals in 93.8% (132/135) patients could be predicted accurately by Doppler analysis. If the optimal reconstruction intervals predicted by Doppler were applied as the exposure windows, the mean length of pulsing windows should has been 105.2 ± 69.4 ms (range: 26.9–510.3 ms), which was significantly shorter than that of traditional prospective ECG-gating protocol (232.0 ± 120.2 ms, range: 93.2–427.3 ms, P < 0.001). Conclusion: Doppler can help detecting the optimal pulsing windows accurately. Prospective ECG-gating incorporating Doppler analysis may narrow pulsing windows significantly while maintaining image quality.

  18. Transthoracic Doppler echocardiography to predict optimal tube pulsing window for coronary artery CT angiography

    International Nuclear Information System (INIS)

    Sun, Gang; Li, Min; Jiang, Xiang-sen; Li, Li; Peng, Zhao-hui; Mu, Nan-nan

    2012-01-01

    Rationale and objective: To evaluate the feasibility of transthoracic Doppler echocardiography to determine the optimal pulsing windows for CT coronary angiography to narrow the pulsing windows further, especially in higher heart rate. Materials and methods: Doppler was performed on 135 patients before CT scanning. For Doppler, the intervals with minimal motion were evaluated during both systole and diastole integrating electrocardiogram (ECG) intervals. For CT scanning, the retrospective ECG-gating was applied and the optimal reconstruction intervals were determined. The accuracy of Doppler analysis to predict the optimal reconstruction intervals was tested. The predicted length of pulsing windows was compared between Doppler analysis and traditional prospective ECG-gating protocol (heart rate ≦ 65 bpm, 60–76%; 66–79 bpm, 30–77%; ≧80 bpm, 31–47%). Results: According to Doppler analysis, the mean length of intervals with minimal motion in systole was 106.4 ± 39.2 ms and 125.2 ± 92.0 ms in diastole. When the intervals with minimal motion during diastole > 90 ms, the optimal reconstruction intervals were located at diastole; otherwise, at systole (P < 0.001). The optimal reconstruction intervals in 93.8% (132/135) patients could be predicted accurately by Doppler analysis. If the optimal reconstruction intervals predicted by Doppler were applied as the exposure windows, the mean length of pulsing windows should has been 105.2 ± 69.4 ms (range: 26.9–510.3 ms), which was significantly shorter than that of traditional prospective ECG-gating protocol (232.0 ± 120.2 ms, range: 93.2–427.3 ms, P < 0.001). Conclusion: Doppler can help detecting the optimal pulsing windows accurately. Prospective ECG-gating incorporating Doppler analysis may narrow pulsing windows significantly while maintaining image quality

  19. TRIPLEX DOPPLER DA ARTÉRIA HEPÁTICA CANINA NOS PERÍODOS PRÉ E PÓS-PRANDIAL TRIPLEX DOPPLER OF CANINE HEPATIC ARTERY ON PRE AND POSPRANDIAL PERIODS

    Directory of Open Access Journals (Sweden)

    Elizabete Nikolak Nikolak

    2009-09-01

    Full Text Available O objetivo deste trabalho foi avaliar por meio do triplex doppler as varia��ões dos índices de resistividade (IR e pulsatilidade (IP da artéria hepática (AH de cães adultos saudáveis em períodos pré e pós-prandiais. O grupo amostral foi composto por quatorze cães sem raça definida, sendo nove fêmeas e cinco machos com peso entre seis e dezenove quilos e quatro e dezesseis quilos, respectivamente. Previamente aos exames ultrassonográficos, os animais foram submetidos a 24 horas de jejum e, para os exames pós-prandiais, foram alimentados com leite ou ração comercial. Utilizou-se o ultrassom Philips HDI 4000, munido de um transdutor microconvexo (5-8MHz. Dividiram-se as mensurações dos IR e IP da AH em três tempos: T0 (período pré-prandial, T1 (trinta minutos pós-prandial e T2 (noventa minutos pós-prandial. Não houve diferença estatística quando comparadas as médias de IR e IP da AH entre T0 e T2. No entanto, ambos os índices foram significativamente menores no T1 quando comparado com os outros períodos de análise, comprovando aumento de fluxo sanguíneo na AH trinta minutos pós-prandial. O uso do triplex doppler da AH possibilitou mensurações do fluxo sanguíneo pré e pós-prandial, sendo uma técnica importante para estabelecer parâmetros comparativos entre homeostasia metabólica e diferentes estados fisiopatológicos hepáticos.

    PALAVRAS-CHAVES: Artéria hepática, cães, índice de resistividade, índice de pulsatilidade, ultrassonografia. The aim of the current study was to evaluate the resistivity index (RI and pulsatility index (PI of hepatic artery (HA by Triplex Doppler in health adult dogs on pre and postprandial periods. The experimental group was formed by 14 mongrel dogs, 9 females and five males, weighing 6-19 kg and 4-16 kg, respectively. The animals were previously prepared, remaining 24 hours of starvation, and feeding with milk or pellet show food to perform posprandial analysis

  20. High-frequency dual mode pulsed wave Doppler imaging for monitoring the functional regeneration of adult zebrafish hearts

    OpenAIRE

    Kang, Bong Jin; Park, Jinhyoung; Kim, Jieun; Kim, Hyung Ham; Lee, Changyang; Hwang, Jae Youn; Lien, Ching-Ling; Shung, K. Kirk

    2015-01-01

    Adult zebrafish is a well-known small animal model for studying heart regeneration. Although the regeneration of scars made by resecting the ventricular apex has been visualized with histological methods, there is no adequate imaging tool for tracking the functional recovery of the damaged heart. For this reason, high-frequency Doppler echocardiography using dual mode pulsed wave Doppler, which provides both tissue Doppler (TD) and Doppler flow in a same cardiac cycle, is developed with a 30 ...

  1. Desajuste educativo por regiones en Colombia: ¿competencia por salarios o por puestos de trabajo?

    Directory of Open Access Journals (Sweden)

    Castillo Caicedo Maribel

    2007-08-01

    Full Text Available Este trabajo aporta una perspectiva del fenómeno de la sobreeducación,
    entendida como un desajuste por exceso, entre el nivel educativo alcanzado
    por el individuo y el exigido por el puesto de trabajo en el cual se
    desempeña; esto se debe a que existe una demanda laboral estrecha de
    puestos de trabajo para personas calificadas en Colombia. Se analizan las
    contribuciones empíricas existentes y el debate sobre las mismas; se
    examinan las teorías que permiten explicar la existencia de un desajuste
    educativo y se realiza una revisión de la literatura internacional y
    nacional sobre el tema. Adicionalmente, se plantean una serie de hipótesis
    para desarrollar un esquema que permita determinar el comportamiento
    del individuo en el fenómeno de la sobreeducación.

  2. CO2 measurements during transcranial Doppler examinations in headache patients

    DEFF Research Database (Denmark)

    Thomsen, L L; Iversen, Helle Klingenberg

    1994-01-01

    Transcranial Doppler (TCD) examinations are increasingly being used in studies of headache pathophysiology. Because blood velocity is highly dependent on PCO2, these parameters should be measured simultaneously. The most common way of performing measurements during TCD examinations is as end......-tidal pCO2 with a capnograph. When patients are nauseated and vomit, as in migraine, the mask or mouthpiece connected to the capnograph represents a problem. We therefore evaluated whether a transcutaneous pCO2 electrode was as useful as the capnograph for pCO2 measurements in TCD examinations. We...... conclude that this is not the case, and recommend capnographic end-tidal pCO2 measurements during TCD examinations. However, transcutaneous pCO2 measurements may represent a supplement to spot measurements of end-tidal pCO2 in stable conditions when long-term monitoring is needed, and the mask...

  3. Color-flow Doppler imaging in suspected extremity venous thrombosis

    International Nuclear Information System (INIS)

    Foley, W.D.; Middleton, W.D.; Lawson, T.L.; Hinson, G.W.; Puller, D.R.

    1987-01-01

    Color-flow Doppler imaging (CFDI) (Quanatum, 5 and 7.5 MHz, linear array) has been performed on 23 extremities (nine positive for venous thrombosis, 14 negative) with venographic correlation. CFDI criteria evaluated were venous color-flow respiratory variation, augmentation, compressibility, valve competence, and intraluminal echogenic filling defects. Both CFDI and venography were evaluated independently and prospectively. CFDI and venography agreed in all six cases of femoral vein thrombosis and eight of nine cases of popliteal vein thrombosis. CFDI was negative in one instance of recanalized popliteal vein thrombosis. Recanalized femoral vein thrombosis was documented in three patients by CFDI when the vein was nonopacified on conventional venography. CFDI provides a rapid and accurate assessment of the femoral popliteal venous system and can distinguish an occluded from a recanalized thrombus. Initial experience with auxiliary subclavian venous thrombus has produced equally accurate results

  4. Optimized coincidence Doppler broadening spectroscopy using deconvolution algorithms

    International Nuclear Information System (INIS)

    Ho, K.F.; Ching, H.M.; Cheng, K.W.; Beling, C.D.; Fung, S.; Ng, K.P.

    2004-01-01

    In the last few years a number of excellent deconvolution algorithms have been developed for use in ''de-blurring'' 2D images. Here we report briefly on one such algorithm we have studied which uses the non-negativity constraint to optimize the regularization and which is applied to the 2D image like data produced in Coincidence Doppler Broadening Spectroscopy (CDBS). The system instrumental resolution functions are obtained using the 514 keV line from 85 Sr. The technique when applied to a series of well annealed polycrystalline metals gives two photon momentum data on a quality comparable to that obtainable using 1D Angular Correlation of Annihilation Radiation (ACAR). (orig.)

  5. WAMDII: The Wide Angle Michelson Doppler Imaging Interferometer

    Science.gov (United States)

    1992-01-01

    As part of an effort to learn more about the upper atmosphere and how it is linked to the weather experienced each day, NASA and NRCC are jointly sponsoring the Wide Angle Michelson Doppler Imaging Interferometer (WAMDII) Mission. WAMDII will measure atmospheric temperature and wind speed in the upper atmosphere. In addition to providing data on the upper atmosphere, the wind speed and temperature readings WAMDII takes will also be highly useful in developing and updating computer simulated models of the upper atmosphere. These models are used in the design and testing of equipment and software for Shuttles, satellites, and reentry vehicles. In making its wind speed and temperature measurements, WAMDII examines the Earth's airglow, a faint photochemical luminescence caused by the influx of solar ultraviolet energy into the upper atmosphere. During periods of high solar flare activity, the amount of this UV energy entering the upper atmosphere increases, and this increase may effect airglow emissions.

  6. Wide angle Michelson Doppler imaging interferometer. [measuring atmospheric emissions

    Science.gov (United States)

    Shepherd, G. G.

    1980-01-01

    The optical system, stepping control, phase and modulation depth, array detector, and directions sensor are described for a specialized type of Michelson interferometer which works at sufficiently high resolution to measure the line widths and Doppler shifts of naturally occurring atmospheric emissions. With its imaging capability, the instrument can potentially supply this data independently for each element of the 100 x 100 detector array. The experiment seeks: (1) to obtain vertical profiles of atmospheric winds and temperatures as functions of latitude by observing near the limb; (2) to acquire exploratory wind and temperature data on smaller scale structures in airglow irregularities and in auroral forms; and (3) to collaborate with other Spacelab experiments, such as barium cloud releases, in providing wind and temperature data.

  7. Doppler frequency in interplanetary radar and general relativity

    Science.gov (United States)

    Mcvittie, G. C.

    1972-01-01

    The change of frequency of an interplanetary radar signal sent from the earth to another planet or to a space probe is worked out according to general relativity. The Schwarzschild spacetime is employed and its null geodesics control the motion of the signals. Exact Doppler frequency formulas are derived for one-way and two-way radar in terms of an arbitrary Schwarzschild radial coordinate. A reduction to the special relativity case is used to interpret the formulas in terms of the relative radial velocity of emitter and target. The general relativity corrections are worked out approximately for each of three possible Schwarzschild radial coordinates, and a numerical example is given. The amount of the correction is different according as one or the other of the Schwarzschild coordinates is identified with the radius vector deduced from classical celestial mechanics. The identification problem is discussed.

  8. Muerte materna por malaria grave por Plasmodium vivax

    Directory of Open Access Journals (Sweden)

    Nancy Arróspide

    Full Text Available Se presenta el caso de una mujer de 19 años con 29 semanas de gestación, procedente de Llumpe (Ancash con antecedentes de viajes a las localidades de Chanchamayo (Junín y Rinconada (Ancash. Ingresó al Hospital de Chacas (Ancash por presentar mal estado general, deshidratación, dificultad respiratoria, ictericia, sensación de alza térmica y dolor abdominal, tuvo reporte de: hemoparásitos 60% en frotis sanguíneo. Fue transferida al Hospital Ramos Guardia (Huaraz donde presentó mayor dificultad respiratoria, coluria, hematuria, disminución del débito urinario y reporte de Plasmodium (+, luego fue transferida al Hospital Cayetano Heredia (Lima donde ingresó a la Unidad de Cuidados Intensivos (UCI, con evolución a falla multiorgánica, óbito fetal y muerte materna. Se confirmó infección por Plasmodium vivax. Destacamos la importancia de mejorar nuestras capacidades de diagnóstico y manejo para brindar un tratamiento adecuado y oportuno.

  9. Measurement of ciliary beat frequency using Doppler optical coherence tomography.

    Science.gov (United States)

    Lemieux, Bryan T; Chen, Jason J; Jing, Joseph; Chen, Zhongping; Wong, Brian J F

    2015-11-01

    Measuring ciliary beat frequency (CBF) is a technical challenge and difficult to perform in vivo. Doppler optical coherence tomography (D-OCT) is a mesoscopic noncontact imaging modality that provides high-resolution tomographic images and detects micromotion simultaneously in living tissues. In this work we used D-OCT to measure CBF in ex vivo tissue as the first step toward translating this technology to clinical use. Fresh ex vivo samples of rabbit tracheal mucosa were imaged using both D-OCT and phase-contrast microscopy (n = 5). The D-OCT system was designed and built to specification in our lab (1310-nm swept source vertical-cavity surface-emitting laser [VCSEL], 6-μm axial resolution). The samples were placed in culture and incubated at 37°C. A fast Fourier transform was performed on the D-OCT signal recorded on the surface of the samples to gauge CBF. High-speed digital video of the epithelium recorded via phase-contrast microscopy was analyzed to confirm the CBF measurements. The D-OCT system detected Doppler signal at the epithelial layer of ex vivo rabbit tracheal samples suggestive of ciliary motion. CBF was measured at 9.36 ± 1.22 Hz using D-OCT and 9.08 ± 0.48 Hz using phase-contrast microscopy. No significant differences were found between the 2 methods (p > 0.05). D-OCT allows for the quantitative measurement of CBF without the need to resolve individual cilia. Furthermore, D-OCT technology can be incorporated into endoscopic platforms that allow clinicians to readily measure CBF in the office and provide a direct measurement of mucosal health. © 2015 ARS-AAOA, LLC.

  10. Bubble-Induced Color Doppler Feedback for Histotripsy Tissue Fractionation.

    Science.gov (United States)

    Miller, Ryan M; Zhang, Xi; Maxwell, Adam D; Cain, Charles A; Xu, Zhen

    2016-03-01

    Histotripsy therapy produces cavitating bubble clouds to increasingly fractionate and eventually liquefy tissue using high-intensity ultrasound pulses. Following cavitation generated by each pulse, coherent motion of the cavitation residual nuclei can be detected using metrics formed from ultrasound color Doppler acquisitions. In this paper, three experiments were performed to investigate the characteristics of this motion as real-time feedback on histotripsy tissue fractionation. In the first experiment, bubble-induced color Doppler (BCD) and particle image velocimetry (PIV) analysis monitored the residual cavitation nuclei in the treatment region in an agarose tissue phantom treated with two-cycle histotripsy pulses at [Formula: see text] using a 500-kHz transducer. Both BCD and PIV results showed brief chaotic motion of the residual nuclei followed by coherent motion first moving away from the transducer and then rebounding back. Velocity measurements from both PIV and BCD agreed well, showing a monotonic increase in rebound time up to a saturation point for increased therapy dose. In a second experiment, a thin layer of red blood cells (RBC) was added to the phantom to allow quantification of the fractionation of the RBC layer to compare with BCD metrics. A strong linear correlation was observed between the fractionation level and the time to BCD peak rebound velocity over histotripsy treatment. Finally, the correlation between BCD feedback and histotripsy tissue fractionation was validated in ex vivo porcine liver evaluated histologically. BCD metrics showed strong linear correlation with fractionation progression, suggesting that BCD provides useful quantitative real-time feedback on histotripsy treatment progression.

  11. Wind turbine wake visualization and characteristics analysis by Doppler lidar.

    Science.gov (United States)

    Wu, Songhua; Liu, Bingyi; Liu, Jintao; Zhai, Xiaochun; Feng, Changzhong; Wang, Guining; Zhang, Hongwei; Yin, Jiaping; Wang, Xitao; Li, Rongzhong; Gallacher, Daniel

    2016-05-16

    Wind power generation is growing fast as one of the most promising renewable energy sources that can serve as an alternative to fossil fuel-generated electricity. When the wind turbine generator (WTG) extracts power from the wind, the wake evolves and leads to a considerable reduction in the efficiency of the actual power generation. Furthermore, the wake effect can lead to the increase of turbulence induced fatigue loads that reduce the life time of WTGs. In this work, a pulsed coherent Doppler lidar (PCDL) has been developed and deployed to visualize wind turbine wakes and to characterize the geometry and dynamics of wakes. As compared with the commercial off-the-shelf coherent lidars, the PCDL in this work has higher updating rate of 4 Hz and variable physical spatial resolution from 15 to 60 m, which improves its capability to observation the instantaneous turbulent wind field. The wind speed estimation method from the arc scan technique was evaluated in comparison with wind mast measurements. Field experiments were performed to study the turbulent wind field in the vicinity of operating WTGs in the onshore and offshore wind parks from 2013 to 2015. Techniques based on a single and a dual Doppler lidar were employed for elucidating main features of turbine wakes, including wind velocity deficit, wake dimension, velocity profile, 2D wind vector with resolution of 10 m, turbulence dissipation rate and turbulence intensity under different conditions of surface roughness. The paper shows that the PCDL is a practical tool for wind energy research and will provide a significant basis for wind farm site selection, design and optimization.

  12. Ovarian and uterine periovulatory Doppler ultrasonography in bitches

    Directory of Open Access Journals (Sweden)

    Claudia C. Barbosa

    2013-09-01

    Full Text Available This paper aims to describe the uterine and ovarian ultrasonographic characteristics and Doppler velocimetric features of their arteries in bitches during the periovulatory period. Fifteen estrous cycles in 10 animals were evaluated. The ultrasonographic characteristics, resistance indices (RI and pulsatility indices (PI of the uterus and ovaries in each animal were recorded 5 days before and after ovulation (D0. The data were statistically analyzed, and the results were expressed as the mean ± standard error of mean (P<0.05. In results the ultrasonographic features of the uterus were the same on all of the cycles and evaluated days. The uterus had an average diameter of 0.85±0.02cm. An increase in the volume of the ovaries and the diameter of the ovarian follicles were measured. Ovaries had a volume of 0.64±0.06cm³, and the follicles cavities had a diameter of 0.46 ± 0.01 cm on the day of ovulation. After ovulation, it was observed that some follicles not collapse in some cycles. Two days prior to ovulation, the uterine blood perfusion decreased. This decrease remained unchanged until ovulation. Following ovulation, we measured a gradual increase in the uterine perfusion and in the ovarian artery. This artery directed blood flow to the ovaries and increased the intra-ovarian perfusion on the day after ovulation. In conclusion, specific features are observed in the uterus and ovarian ultrasound image and Doppler values of their arteries presented on the periovulatory days and when associated allow to estimate more accurately the date of ovulation.

  13. Power and color Doppler ultrasound settings for inflammatory flow: impact on scoring of disease activity in patients with rheumatoid arthritis.

    Science.gov (United States)

    Torp-Pedersen, Søren; Christensen, Robin; Szkudlarek, Marcin; Ellegaard, Karen; D'Agostino, Maria Antonietta; Iagnocco, Annamaria; Naredo, Esperanza; Balint, Peter; Wakefield, Richard J; Torp-Pedersen, Arendse; Terslev, Lene

    2015-02-01

    To determine how settings for power and color Doppler ultrasound sensitivity vary on different high- and intermediate-range ultrasound machines and to evaluate the impact of these changes on Doppler scoring of inflamed joints. Six different types of ultrasound machines were used. On each machine, the factory setting for superficial musculoskeletal scanning was used unchanged for both color and power Doppler modalities. The settings were then adjusted for increased Doppler sensitivity, and these settings were designated study settings. Eleven patients with rheumatoid arthritis (RA) with wrist involvement were scanned on the 6 machines, each with 4 settings, generating 264 Doppler images for scoring and color quantification. Doppler sensitivity was measured with a quantitative assessment of Doppler activity: color fraction. Higher color fraction indicated higher sensitivity. Power Doppler was more sensitive on half of the machines, whereas color Doppler was more sensitive on the other half, using both factory settings and study settings. There was an average increase in Doppler sensitivity, despite modality, of 78% when study settings were applied. Over the 6 machines, 2 Doppler modalities, and 2 settings, the grades for each of 7 of the patients varied between 0 and 3, while the grades for each of the other 4 patients varied between 0 and 2. The effect of using different machines, Doppler modalities, and settings has a considerable influence on the quantification of inflammation by ultrasound in RA patients, and this must be taken into account in multicenter studies. Copyright © 2015 by the American College of Rheumatology.

  14. Miasis ocular por Oestrus ovis

    Directory of Open Access Journals (Sweden)

    María Beltrán F

    2006-01-01

    Full Text Available Se presentan tres casos de miasis ocular (dos adultos y un niñoprocedentes de zonas ganaderas de la provincia de Huaura,departamento de Lima,que acudieron al Hospital Regional de Huacho por presentar el ojo rojo,fotofobia, edema palpebral y sensación de cuerpo extraño;se extrajeron larvas adheridas al canto interno del ojo,las cuales se recibieron en el Instituto Nacional de Salud y fueron identificadas como Oestrus ovis .

  15. Hipoglucemia inducida por carcinoma adrenal

    Directory of Open Access Journals (Sweden)

    Jimena Soutelo

    2013-08-01

    Full Text Available El carcinoma suprarrenal es una neoplasia maligna infrecuente y de mal pronóstico. La presentación clínica más común es originada por la producción hormonal excesiva, mientras que el desarrollo de hipoglucemia sintomática es excepcional. Presentamos el caso de una mujer de 37 años que ingresó al hospital por síntomas de hipoglucemias graves, hipertensión arterial, hipopotasemia y amenorrea secundaria. En el laboratorio se halló hipoglucemia con insulina inhibida y niveles de andrógenos en rango tumoral. La tomografía computarizada (TC de abdomen y pelvis mostró voluminosa formación heterogénea de aspecto sólido sin plano de clivaje con respecto al parénquima hepático e intenso realce con contraste. Luego de la extirpación de la masa retroperitoneal, evolucionó con valores de glucemia y potasemia normales, estabilizó la presión arterial y recuperó los ciclos menstruales.

  16. La curiosidad por la naturaleza

    Directory of Open Access Journals (Sweden)

    José Vicente Rodríguez

    2016-07-01

    Full Text Available Esta actitud es un instrumento estratégico para estimular procesos de desarrollo realmente sostenibles, donde se aproveche la admiración que nos embarga al conocer y apreciar lo que nos rodea para responsablemente utilizar y conservar nuestros recursos naturales. Con esta reflexión deseo resaltar esa motivación de escudriñar lo desconocido, que fue también la virtud que propició el desarrollo de la personalidad de Francisco José de Caldas y Tenorio, uno de nuestros primeros y connotados sabios colombianos, y en cuyo honor se constituyó la revista de divulgación científica más importante del país, que en estos momentos cumple 76 años de existencia. Caldas tuvo curiosidad por todo lo que existía en su entorno; inicialmente en su natal Popayán, donde se maravilló por lo natural, lo que lo motivó y llevó más allá de su tierra a formar parte de la mayor empresa de exploración científica adelantada en ese entonces en territorio americano: la primera Expedición Botánica al nuevo Reino de Granada, de José Celestino Mutis.

  17. Doppler sonography of diabetic feet: Quantitative analysis of blood flow volume

    International Nuclear Information System (INIS)

    Seo, Young Lan; Kim, Ho Chul; Choi, Chul Soon; Yoon, Dae Young; Han, Dae Hee; Moon, Jeung Hee; Bae, Sang Hoon

    2002-01-01

    To analyze Doppler sonographic findings of diabetic feet by estimating the quantitative blood flow volume and by analyzing waveform on Doppler. Doppler sonography was performed in thirty four patients (10 diabetic patients with foot ulceration, 14 diabetic patients without ulceration and 10 normal patients as the normal control group) to measure the flow volume of the arteries of the lower extremities (posterior and anterior tibial arteries, and distal femoral artery. Analysis of doppler waveforms was also done to evaluate the nature of the changed blood flow volume of diabetic patients, and the waveforms were classified into triphasic, biphasic-1, biphasic-2 and monophasic patterns. Flow volume of arteries in diabetic patients with foot ulceration was increased witha statistical significance when compared to that of diabetes patients without foot ulceration of that of normal control group (P<0.05). Analysis of Doppler waveform revealed that the frequency of biphasic-2 pattern was significantly higher in diabetic patients than in normal control group(p<0.05). Doppler sonography in diabetic feet showed increased flow volume and biphasic Doppler waveform, and these findings suggest neuropathy rather than ischemic changes in diabetic feet.

  18. Analysis of placenta vascularization in patients with uterine altered artery Doppler flow velocity exams.

    Science.gov (United States)

    Gilio, Daniel Bruno; Miranda Corrêa, Rosana Rosa; Souza de Oliveira Guimarães, Camila; Peres, Luiz Cesar; Marques Salge, Ana Karina; Cavellani, Camila Lourencini; de Paula Antunes Teixeira, Vicente; Costa da Cunha Castro, Eumenia

    2009-08-01

    One of the frequent questions in obstetric practice is to determine placental vascular changes that may account for abnormal Doppler flow velocity alterations in maternal uterine vessels from women and fetuses without pregnancy pathology. A retrospective morphometric study was realized using 27 placentas from patients submitted for Doppler flow velocity exam during pregnancy. The placentas were morphologically examined using hematoxylin-eosin staining. Measurements of villi were made with the use of a video camera coupled to a common light microscope and a computer with automatic image analyzing software. Of the 27 placentas, 13 (48%) were of patients showing unaltered Doppler and 14 (52%) showing altered Doppler. The number of stem villi vessels was significantly larger in the placentas of patients with Doppler exam alterations (P = 0.003). This group also presented greater stem villi vessel thickness, although without significant difference. The number of intermediary and terminal villi vessels was greater in the placentas of patients with altered Doppler exams (P < 0.001), and a greater terminal villi area was observed in these cases (P < 0.001). The morphological proof that uterine artery Doppler flow velocity exam alterations are associated with placental vascular alterations demonstrates the importance of this exam during prenatal care, even in the absence of maternal-fetal alterations.

  19. [Diagnostic value of power Doppler ultrasonography for Sirenomelia Seguence in prenatal].

    Science.gov (United States)

    Yan, Xia-yu; Yang, Tai-zhu; Luo, Hong; Tian, Yu; Yang, Fan

    2011-11-01

    To study and discuss the diagnostic value and ultrasonographic characteristics of power doppler ultrasound in the prenatal diagnosis of Sirenomelia Seguence. The abdominal aorta in two fetuses with sirenomelia seguence fetuses and in ten with nomal was reviewed and compared with two-dimensional power doppler ultrasound and three-dimensional power doppler ultrasound in prenatal. The abdominal aorta were showed to divid into renal arteries in the kidney level while two common iliac arteries in the pelvis in nomal fetuses with two-dimensional power doppler ultrasound and three-dimensional power doppler ultrasound; compared with the nomal, the abdominal aorta and whose branches in sirenomelia seguence were demonstrated as follows: 1) a large and deformed vascular coming from the high abdominal aorta, which was found to act as a umbilical artery by careful examination; 2) no bifurcation of renal arteries identified; 3) no bifurcation of two common iliac arteries identified; 4) the abdominal aorta changing into a narrow vascular after one deformed vascular separating from. Sirenomelia seguence fetuses has a characteristic change in two-dimensional power doppler ultrasound and three-dimensional power doppler ultrasound, which is helpful to improve the prenatal diagnosis of sirenomelia seguence.

  20. Deep vein thrombosis of lower extremity: What is the most important finding in duplex Doppler sonography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Soo; Koh, Byung Hee; Cho, On Koo; Rhim, Hyun Chul; Seo, Heung Suk; Hahm, Chang Kok; Kwak, Jin Young [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    1993-12-15

    The positive findings of deep vein thrombosis on duplex Doppler ultrasonography such as intraluminal clot,non-compressibility of the venous lumen and abnormal or absent Doppler shift signal are well known. However, relatively hypoechoic thrombus is not always seen in sonography, and the vein is frequently compressible in partial thrombosis. In order to evaluate the most common and important findings of deep vein thrombosis, we analysed the findings at duplex Doppler ultrasound in 19 patients and compared the results with those of contrast venography in 11 patients. Duplex Doppler ultrasound examination of the common femoral and popliteal veins was performed for one extremity in 14 patients, and for both extremities in 5 (total 24 extremities). Contrast venography was performed for one extremity in 7 patients, and for both sides in 4 (total 15 extremities).Thrombosis was seen in 45.8%, non-compressibility of lumen in 75%, absent or decreased Doppler signal from common femoral vein in 95.8%. Thrombosis was seen in 41.7%, non-compressibility of lumen in 70.8%, absent or decreased Doppler shift signal from popliteal vein in 95.8%. We conclude that abnormal or absent Doppler shift signal is the most sensitive and important finding of the deep vein thrombosis

  1. Doppler sonography of diabetic feet: Quantitative analysis of blood flow volume

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Young Lan; Kim, Ho Chul; Choi, Chul Soon; Yoon, Dae Young; Han, Dae Hee; Moon, Jeung Hee; Bae, Sang Hoon [Hallym University College of Medicine, Seoul (Korea, Republic of)

    2002-09-15

    To analyze Doppler sonographic findings of diabetic feet by estimating the quantitative blood flow volume and by analyzing waveform on Doppler. Doppler sonography was performed in thirty four patients (10 diabetic patients with foot ulceration, 14 diabetic patients without ulceration and 10 normal patients as the normal control group) to measure the flow volume of the arteries of the lower extremities (posterior and anterior tibial arteries, and distal femoral artery. Analysis of doppler waveforms was also done to evaluate the nature of the changed blood flow volume of diabetic patients, and the waveforms were classified into triphasic, biphasic-1, biphasic-2 and monophasic patterns. Flow volume of arteries in diabetic patients with foot ulceration was increased witha statistical significance when compared to that of diabetes patients without foot ulceration of that of normal control group (P<0.05). Analysis of Doppler waveform revealed that the frequency of biphasic-2 pattern was significantly higher in diabetic patients than in normal control group(p<0.05). Doppler sonography in diabetic feet showed increased flow volume and biphasic Doppler waveform, and these findings suggest neuropathy rather than ischemic changes in diabetic feet.

  2. Color Doppler flow mapping of stenotic and regurgitant natural heart valves

    International Nuclear Information System (INIS)

    Nanda, N.C.

    1986-01-01

    Color Doppler echocardiography has found widest application in reliable detection and assessment of severity of both atrio-ventricular and semi-lunar valve incompetence. The authors believe both the sensitivity and specificity of color Doppler for the detection of mitral and aortic regurgitation is very high in patients with adequate acoustic windows. In 82 patients with proven mitral regurgitation studied, the best correlations with angiography were noted when the maximum or average regurgitant jet are obtained by color Doppler from three standard 2-D echo planes (parasternal long and short axis and apical four chamber view) and expressed as a percentage of the left atrial area were considered. The criteria the authors used for assessment of tricuspid and pulmonary valve incompetence are similar to those used for mitral and aortic valve incompetence, but the lack of a good ''gold'' standard has hampered validation. The color Doppler technique also supplements conventional Doppler in the assessment of severity of stenotic lesions by facilitating parallel alignment of the continuous wave Doppler cursor line with the stenotic jet for accurate recording of maximal velocities and pressure gradients. The authors have found this method especially useful in the assessment of aortic stenosis. In conclusion, color Doppler flow mapping combined with conventional echocardiography provides, for the first time, a comprehensive noninvasive assessement of the severity of regurgitant and stenotic lesions

  3. Quality-Controlled Wind Data from the Kennedy Space Center 915 Megahertz Doppler Radar Wind Profiler Network

    Science.gov (United States)

    Dryden, Rachel L.

    2011-01-01

    The National Aeronautics and Space Administration s (NASA) Kennedy Space Center (KSC) has installed a five-instrument 915-Megahertz (MHz) Doppler Radar Wind Profiler (DRWP) system that records atmospheric wind profile properties. The purpose of these profilers is to fill data gaps between the top of the KSC wind tower network and the lowest measurement altitude of the KSC 50-MHz DRWP. The 915-MHz DRWP system has the capability to generate three-dimensional wind data outputs from approximately 150 meters (m) to 6,000 m at roughly 15-minute (min) intervals. NASA s long-term objective is to combine the 915-MHz and 50-MHz DRWP systems to create complete vertical wind profiles up to 18,300 m to be used in trajectory and loads analyses of space vehicles and by forecasters on day-of-launch (DOL). This analysis utilizes automated and manual quality control (QC) processes to remove erroneous and unrealistic wind data returned by the 915-MHz DRWP system. The percentage of data affected by each individual QC check in the period of record (POR) (i.e., January to April 2006) was computed, demonstrating the variability in the amount of data affected by the QC processes. The number of complete wind profiles available at given altitude thresholds for each profiler in the POR was calculated and outputted graphically, followed by an assessment of the number of complete wind profiles available for any profiler in the POR. A case study is also provided to demonstrate the QC process on a day of a known weather event.

  4. Mortalidad por meningitis por Pasteurella canis. Oportunidades de aprendizaje

    Directory of Open Access Journals (Sweden)

    Ana Rosa Ropero Vera

    2016-01-01

    Full Text Available La meningitis bacteriana es una enfermedad importante de distribución mundial, causa mayor y sustancial de mortalidad y morbilidad en países en desarrollo. La Organización Mundial de la Salud (OMS sostiene que la meningitis es una de las diez afecciones principales del ser humano y debe ser considerada como una emergencia infectológica; por eso es fundamental reconocer que esta enfermedad es causa de muerte en niños de todo el mundo, sin distinción de raza, nivel económico o sociocultural. Se realizó una investigación de caso en menor de 53 días de nacido, que cumplía con los criterios clínicos y de laboratorio compatible con meningitis bacteriana, con el propósito de analizar y fortalecer la toma de decisiones en salud pública por parte de la secretaría local de salud del municipio de Valledupar (Colombia. Entre los hallazgos se encontró antecedentes infecciosos en el menor, coloración de Gram y cultivo de LCR, en el que se identificó cocobacilos Gram negativos, que fueron aislados como agente causal Pasteurella canis. Este estudio pretende sensibilizar a los prestadores de salud para que cuenten con personal altamente capacitado para brindar tratamientos adecuados y prevenir complicaciones en la meningitis bacteriana en niños, y así disminuir la posibilidad de secuelas o muerte, tanto en pacientes con compromiso inmunológico o sin este.

  5. Three-dimensional power Doppler sonography in screening for carotid artery disease.

    Science.gov (United States)

    Keberle, M; Jenett, M; Beissert, M; Jahns, R; Haerten, R; Hahn, D

    2000-01-01

    Color Doppler sonography has gained considerable recognition as a noninvasive method to detect carotid artery disease and to assess the degree of carotid artery stenosis. However, results are highly operator-dependent and cannot be presented as survey images. The purpose of this study was to evaluate real-time 3-dimensional (3D) power Doppler sonography as a method for screening for atherosclerosis in the carotid arteries. We prospectively screened 75 patients for carotid artery disease using both conventional color Doppler sonography and 3D power Doppler sonography, and the results from the 2 modalities were compared. A total of 150 common carotid arteries, 150 internal carotid arteries, and 150 external carotid arteries were examined utilizing a 7.5-MHz linear-array transducer combined with tissue harmonic imaging. Color Doppler sonography detected 297 normal or atherosclerotic arteries without stenosis, 57 arteries with mild (1-49%) stenosis, 41 with moderate (50-69%) stenosis, 32 with severe (70-99%) stenosis, and 9 with occlusions. The degree of stenosis determined by color Doppler sonography correlated with that determined by 3D power Doppler sonography (r = 0.982-0.998). Moreover, there was a good correlation between the measurements for both the length of the lesion and its distance from the bulb as determined by the 3D volume surveys and by color Doppler sonography (r = 0.986). The interobserver variability rate was 3.7% +/- 0.5%. Generally, the acquisition and reconstruction of the 3D data took less than 5 minutes. 3D power Doppler sonography is easy to perform and is an accurate method in screening for atherosclerotic lesions of the carotid arteries. Moreover, it provides excellent 3D volume surveys that may be helpful in the planning of surgical treatment. Copyright 2000 John Wiley & Sons, Inc.

  6. Developments in target micro-Doppler signatures analysis: radar imaging, ultrasound and through-the-wall radar

    OpenAIRE

    Clemente, C.; Balleri, A.; Woodbridge, K.; Soraghan, J. J.

    2013-01-01

    Target motions, other than the main bulk translation of the target, induce Doppler modulations around the main Doppler shift that form what is commonly called a target micro-Doppler signature. Radar micro-Doppler signatures are generally both target and action speci c and hence can be used to classify and recognise targets as well as to identify possible threats. In recent years, research into the use of micro-Doppler signatures for target classi cation to address many defence and security ch...

  7. Analytical Model of Doppler Spectra of Light Backscattered from Rotating Convex Bodies of Revolution in the Global Cartesian Coordinate System

    International Nuclear Information System (INIS)

    Yan-Jun, Gong; Zhen-Sen, Wu; Jia-Ji, Wu

    2009-01-01

    We present an analytical model of Doppler spectra in backscattering from arbitrary rough convex bodies of revolution rotating around their axes in the global Cartesian coordinate system. This analytical model is applied to analyse Doppler spectra in backscatter from two cones and two cylinders, as well as two ellipsoids of revolution. We numerically analyse the influences of attitude and geometry size of objects on Doppler spectra. The analytical model can give contribution of the surface roughness, attitude and geometry size of convex bodies of revolution to Doppler spectra and may contribute to laser Doppler velocimetry as well as ladar applications

  8. Application of coincidence Doppler-broadening spectroscopy to different carbon phases

    International Nuclear Information System (INIS)

    Ito, Y.; Djourelov, N.; Suzuki, T.; Kondo, K.; Ito, Y.; Shantarovich, V.; Onoe, J.

    2004-01-01

    Coincidence Doppler-broadening spectroscopy was applied to C60 and C70 fullerenes and other carbon phases, such as nanotubes and graphites. Remarkable differences were observed in the Doppler-broadening of the positron annihilation γ-rays in these materials, which reflect the different densities distribution of the momentum for electrons annihilated with positrons. This would be caused by the different composition of the π and σ electrons in annihilation with positrons. This result shows the sensitivity of the coincidence Doppler-broadening method to determine the density distribution of electrons sampled by positrons. (orig.)

  9. Macroscopic effects in electromagnetically-induced transparency in a Doppler-broadened system

    International Nuclear Information System (INIS)

    Pei Li-Ya; Qu Yi-Zhi; Niu Jin-Yan; Wang Ru-Quan; Wu Ling-An; Fu Pan-Ming; Zuo Zhan-Chun

    2015-01-01

    We study the electromagnetically-induced transparency (EIT) in a Doppler-broadened cascaded three-level system. We decompose the susceptibility responsible for the EIT resonance into a linear and a nonlinear part, and the EIT resonance reflects mainly the characteristics of the nonlinear susceptibility. It is found that the macroscopic polarization interference effect plays a crucial role in determining the EIT resonance spectrum. To obtain a Doppler-free spectrum there must be polarization interference between atoms of different velocities. A dressed-state model, which analyzes the velocities at which the atoms are in resonance with the dressed states through Doppler frequency shifting, is employed to explain the results. (paper)

  10. Applications of Doppler-free saturation spectroscopy for edge physics studies (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Martin, E. H., E-mail: martineh@ornl.gov; Caughman, J. B. O.; Isler, R. C.; Bell, G. L. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Zafar, A. [Department of Nuclear Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2016-11-15

    Doppler-free saturation spectroscopy provides a very powerful method to obtain detailed information about the electronic structure of the atom through measurement of the spectral line profile. This is achieved through a significant decrease in the Doppler broadening and essentially an elimination of the instrument broadening inherent to passive spectroscopic techniques. In this paper we present the technique and associated physics of Doppler-free saturation spectroscopy in addition to how one selects the appropriate transition. Simulations of H{sub δ} spectra are presented to illustrate the increased sensitivity to both electric field and electron density measurements.

  11. Effect of Doppler flow meter position on discharge measurement in surcharged manholes.

    Science.gov (United States)

    Yang, Haoming; Zhu, David Z; Liu, Yanchen

    2018-02-01

    Determining the proper installation location of flow meters is important for accurate measurement of discharge in sewer systems. In this study, flow field and flow regimes in two types of manholes under surcharged flow were investigated using a commercial computational fluid dynamics (CFD) code. The error in measuring the flow discharge using a Doppler flow meter (based on the velocity in a Doppler beam) was then estimated. The values of the corrective coefficient were obtained for the Doppler flow meter at different locations under various conditions. Suggestions for selecting installation positions are provided.

  12. The PARAFAC-MUSIC Algorithm for DOA Estimation with Doppler Frequency in a MIMO Radar System

    Directory of Open Access Journals (Sweden)

    Nan Wang

    2014-01-01

    Full Text Available The PARAFAC-MUSIC algorithm is proposed to estimate the direction-of-arrival (DOA of the targets with Doppler frequency in a monostatic MIMO radar system in this paper. To estimate the Doppler frequency, the PARAFAC (parallel factor algorithm is firstly utilized in the proposed algorithm, and after the compensation of Doppler frequency, MUSIC (multiple signal classification algorithm is applied to estimate the DOA. By these two steps, the DOA of moving targets can be estimated successfully. Simulation results show that the proposed PARAFAC-MUSIC algorithm has a higher accuracy than the PARAFAC algorithm and the MUSIC algorithm in DOA estimation.

  13. Investigation of Doppler spectra of laser radiation scattered inside hand skin during occlusion test

    Science.gov (United States)

    Kozlov, I. O.; Zherebtsov, E. A.; Zherebtsova, A. I.; Dremin, V. V.; Dunaev, A. V.

    2017-11-01

    Laser Doppler flowmetry (LDF) is a method widely used in diagnosis of microcirculation diseases. It is well known that information about frequency distribution of Doppler spectrum of the laser radiation scattered by moving red blood cells (RBC) usually disappears after signal processing procedure. Photocurrent’s spectrum distribution contains valuable diagnostic information about velocity distribution of the RBC. In this research it is proposed to compute the indexes of microcirculation in the sub-ranges of the Doppler spectrum as well as investigate the frequency distribution of the computed indexes.

  14. Uncertainty of Doppler reactivity worth due to uncertainties of JENDL-3.2 resonance parameters

    Energy Technology Data Exchange (ETDEWEB)

    Zukeran, Atsushi [Hitachi Ltd., Hitachi, Ibaraki (Japan). Power and Industrial System R and D Div.; Hanaki, Hiroshi; Nakagawa, Tuneo; Shibata, Keiichi; Ishikawa, Makoto

    1998-03-01

    Analytical formula of Resonance Self-shielding Factor (f-factor) is derived from the resonance integral (J-function) based on NR approximation and the analytical expression for Doppler reactivity worth ({rho}) is also obtained by using the result. Uncertainties of the f-factor and Doppler reactivity worth are evaluated on the basis of sensitivity coefficients to the resonance parameters. The uncertainty of the Doppler reactivity worth at 487{sup 0}K is about 4 % for the PNC Large Fast Breeder Reactor. (author)

  15. Three-dimensional Doppler ultrasound findings in healthy wrist and finger tendon sheaths

    DEFF Research Database (Denmark)

    Ammitzboll-Danielsen, Mads; Janta, Iustina; Torp-Pedersen, Søren

    2016-01-01

    interpretation of Doppler signals when diagnosing tenosynovitis. Method Forty healthy participants (20 women and 20 men age 23-67 years) without prior history of arthritis, tendon diseases or present pain in their hands were included. Twenty participants had 3D Doppler US of the second and third finger...... participant. No significant difference in feeding vessels was seen between the radial and carpal level in the wrist (p = 0.06) or between the second and third flexor tendon sheath (p = 0.84). Conclusion Doppler findings in or in close proximity to the tendon sheaths were common in wrists and fingers...

  16. Narrowing of electromagnetically induced transparency resonance in a Doppler-broadened medium

    International Nuclear Information System (INIS)

    Javan, Ali; Kocharovskaya, Olga; Lee Hwang; Scully, Marlan O.

    2002-01-01

    We derive an analytic expression for the linewidth of electromagnetically induced transparency (EIT) resonance in a Doppler-broadened system. It is shown here that for relatively low intensity of the driving field the EIT linewidth is proportional to the square root of intensity and is independent of the Doppler width, similar to the laser-induced line narrowing effect described by Feld and Javan. In the limit of high intensity we recover the usual power-broadening case where the EIT linewidth is proportional to the intensity and inversely proportional to the Doppler width

  17. Mortalidad intrahospitalaria por accidente cerebrovascular

    Directory of Open Access Journals (Sweden)

    Federico Rodríguez Lucci

    2013-08-01

    Full Text Available La mortalidad global por accidente cerebrovascular (ACV ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Stroke de FLENI y los registros institucionales de mortalidad entre los años 2000 y 2010. Los subtipos de ACV isquémicos se clasificaron según criterios TOAST y los ACV hemorrágicos en hematomas intrapanquimatosos, hemorragias subaracnoideas aneurismáticas, malformaciones arteriovenosas y otros hematomas intraparenquimatosos. Se analizaron 1514 pacientes, 1079 (71% con ACV isquémico (grandes vasos 39%, cardioembólicos 27%, lacunares 9%, etiología indeterminada 14%, otras etiologías 11% y 435 (29% con ACV hemorrágico (intraparenquimatosos 27%, hemorragia subaracnoidea 30%, malformaciones arteriovenosas 25% y otros hematomas espontáneos 18%. Se registraron 38 muertes intrahospitalarias (17 ACV isquémicos y 21 ACV hemorrágicos, representando una mortalidad global del 2.5% (1.7% en ACV isquémicos y 4.8% en ACV hemorrágicos. No se registraron muertes asociadas al uso de fibrinolíticos endovenosos. La mortalidad intrahospitalaria en pacientes con ACV isquémico y hemorrágico en nuestro centro fue baja. El manejo en un centro dedicado a las enfermedades neurológicas y el enfoque multidisciplinario por personal médico y no médico entrenado en el cuidado de la enfermedad cerebrovascular podrían explicar, al menos en parte, estos resultados.

  18. Description and evaluation of the CASA dual-Doppler system

    Science.gov (United States)

    Martinez, Matthew

    2011-12-01

    Long range weather surveillance radars are designed for observing weather events for hundreds of kilometers from the radar and operate over a large coverage domain independently of weather conditions. As a result a loss in spatial resolution and limited temporal sampling of the weather phenomenon occurs. Due to the curvature of the Earth, long-range weather radars tend to make the majority of their precipitation and wind observations in the middle to upper troposphere, resulting in missed features associates with severe weather occurring in the lowest three kilometers of the troposphere. The spacing of long-range weather radars in the United States limits the feasibility of using dual-Doppler wind retrievals that would provide valuable information on the kinematics of weather events to end-users and researchers. The National Science Foundation Center for Collaborative Adapting Sensing of the Atmosphere (CASA) aims to change the current weather sensing model by increasing coverage of the lowest three kilometers of the troposphere by using densely spaced networked short-range weather radars. CASA has deployed a network of these radars in south-western Oklahoma, known as Integrated Project 1 (IP1). The individual radars are adaptively steered by an automated system known as the Meteorological Command and Control (MCC). The geometry of the IP1 network is such that the coverage domains of the individual radars are overlapping. A dual-Doppler system has been developed for the IP1 network which takes advantage of the overlapping coverage domains. The system is comprised of two subsystems, scan optimization and wind field retrieval. The scan strategy subsystem uses the DCAS model and the number of dual-Doppler pairs in the IP1 network to minimizes the normalized standard deviation in the wind field retrieval. The scan strategy subsystem also minimizes the synchronization error between two radars. The retrieval itself is comprised of two steps, data resampling and the

  19. Herida precordial por arma blanca

    OpenAIRE

    Marcelo F. Jiménez; Nuria Novoa; José Luis Aranda; Gonzalo Varela

    2005-01-01

    Varón de 42 años con esquizofrenia paranoide. Intento de suicidio con tres autolesiones por arma blanca (Fig. 1). Fue traído al hospital en estado consciente, taquicárdico, taquipneico y con tensión arterial (TA) de 140/90 mmHg. Fue trasladado al quirófano, donde se practicó una toracotomía axilar izquierda sin extraer el arma. Durante la intervención se apreciaron tres heridas incisas, dos no penetrantes, hemotórax de 150 ml, herida pericárdica de 4 cm, sin lesiones cardíacas. La hoja del ar...

  20. [Prognostic Doppler ultrasound examination of fetal arteries blood flow].

    Science.gov (United States)

    Sieroszewski, Piotr; Sabatowska, Małgorzata; Karowicz-Bilińska, Agata; Suzin, Jacek

    2002-08-01

    Early detection of fetal risk is one of the main issues in today obstetrics. Ultrasound diagnostics plays a significant role, as the introduction of Doppler imaging method in the evaluation of blood flow has enabled non-invasive assessment of uteroplacental circulation. Therefore, we have analysed foetal three arteries: umbilical artery, middle cerebral artery and renal artery after determining the normal range for the analysed parameters. 1. Comparison of the obtained blood flow indices (S/D, RI, PI) in the umbilical artery, middle cerebral artery and renal artery of foetuses from normal and complicated full-term pregnancies. 2. Determination of indices: umbilical-cerebral and renal-cerebral in normal and pathological pregnancy. 3. Evaluation of feasibility of the analysed flow parameters for the detection of intrauterine foetal hypoxia. We have examined 151 women, who were divided into control group--101 pregnant women with normal pregnancy and study group--50 pregnant women with complicated pregnancy. All pregnant women underwent ultrasound examination using the Hitachi EUB 515 C (Japan) scanner with 3.5 MHz convex probe, connected to the colour pulsed Doppler. The study consisted of the biometric measurements and evaluation of the spectrum of blood flow in the umbilical artery, middle cerebral artery and renal artery. We have determined following indices: a) systolic-diastolic ratio S/D, resistance index RI, pulsatility index PI, b) umbilical-cerebral ratio P/M. (PI ua/PI mca), renal--cerebral ratio N/M (PI ra/PI mca). Statistically significant difference was found between the study and control groups for all the flow indices assessed (S/D, RI, PI) for the middle cerebral artery, for the indices P/M and N/M. (p < 0.001) and pulsatility index in the renal artery (p < 0.01). Similar, although slightly smaller difference (p < 0.05) was seen for the values of flow parameters in the umbilical artery. 1) Evaluation of blood flow in the middle cerebral artery, and in