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Sample records for tomografia compuatarizada helicoidal

  1. Broncofibroscopia Flexível e Tomografia Helicoidal Computorizada no diagnóstico do Carcinoma Pulmonar Não de Peq uenas Células

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    Ram Cicero

    1998-11-01

    Full Text Available RESUMO: Actualmente a avaliação dos Tumores Pulmonares e as alterações intratorácicas provocadas pelos mesmos pode ser analisada por Tomografia Axial Computorizada e Tomografia Helicoidal Computorizada (THC.Parece haver uma correlação entre as imagens detectadas pela Tomografia Helicoidal Computorizada (THC e as alterações cndoscópicas encontradas por Broncofibroscopia Flexível (BFB.O objectivo deste trabalho foi demonstrar essa eventual correlação.Estudaram-se 18 doentes com Carcinoma do Pulmão Não de Pequenas Células (CPNPC. Houve uma boa correlação da Tomografia Helicoidal Computorizada (THC e dos aspectos encontrados por Broncofibroscopia Flexível (BFB, nas estenoses intrínsecas ou extrínsecas dos Brônquios Principais (BP e Brônquios Lobares (BL.A Tomografa Helicoidal Computorizada (THC pennite a localização espacial do tumor e visualizar as alterações estruturais circunvizinhas secundánas ao crescimento do tumor. A Tomografia Helicoidal Computorizada (THC pennitiu ainda a visualização da árvore brônquica para além da obstrução completa do lúmen brônquico, nos doentes em que não se conseguiu visualizar por broncofibroscopia.Nos tumores periféricos houve demonstração pela Tomografia Helicoidal Computorizada (THC de alterações estruturais da árvore brônquica que por Broncofibroscopia Flexível (BFB foram consideradas normais.Nesta série houve uma correlação directa entre a Tomografia Helicoidal Computorizada (THC e a Broncofibroscopia Flexível (BFB em quinze dos dezoito doentes estudados havendo uma sensibilidade de 83% no diagnóstico do tumor por broncofibroscopia. COMENTÁRIO: A Tomografia Helicoidal Computorizada (THC permite faze r o diagnóstico do cancro do pulmão em três dimensões visualizando as alterações estruturais circunvizinhas.As alterações endoscópicas visualizadas por Broncofibroscopia Flexível (BFB continuam a ser importantes, pela análise macroscópica das lesões e

  2. Reflection of neutrons from a helicoidal system

    International Nuclear Information System (INIS)

    Aksenov, V.L.; Ignatovich, V.K.; Nikitenko, Yu.V.

    2006-01-01

    Analytical solution for neutron reflection and transmission of magnetic mirrors with helicoidal magnetization is found. The dependence of neutron speed of reflection and transmission curves is shown. Resonant properties of helicoidal systems are found

  3. A bioinspired study on the compressive resistance of helicoidal fibre structures.

    Science.gov (United States)

    Tan, Ting; Ribbans, Brian

    2017-10-01

    Helicoidal fibre structures are widely observed in natural materials. In this paper, an integrated experimental and analytical approach was used to investigate the compressive resistance of helicoidal fibre structures. First, helicoidal fibre-reinforced composites were created using three-dimensionally printed helicoids and polymeric matrices, including plain, ring-reinforced and helix-reinforced helicoids. Then, load-displacement curves under monotonic compression tests were collected to measure the compressive strengths of helicoidal fibre composites. Fractographic characterization was performed using an X-ray microtomographer and scanning electron microscope, through which crack propagations in helicoidal structures were illustrated. Finally, mathematical modelling was performed to reveal the essential fibre architectures in the compressive resistance of helicoidal fibre structures. This work reveals that fibre-matrix ratios, helix pitch angles and interlayer rotary angles are critical to the compressive resistance of helicoidal structures.

  4. Helicoidal microstructure of Scarabaei cuticle and biomimetic research

    International Nuclear Information System (INIS)

    Chen, B.; Peng, X.; Cai, C.; Niu, H.; Wu, X.

    2006-01-01

    Insect cuticles as a natural biocomposite include many favorable microstructures which have been refined over centuries and endow the cuticles excellent mechanical and physical properties, such as light weight, high strength and toughness, etc. The various microstructures of a Scarabaei cuticle are investigated with a scanning electronic microscope and reported in this paper. It is found that the cuticle is a kind of fiber-reinforced biocomposite composed of chitin-fiber layers and sclerous protein matrixes. Different chitin-fiber layers have different orientations, composed of crossed and helicoidal structures at different location. In the helicoidal structure, each fiber layer rotates with an almost fixed angle against its neighboring layer. The maximum pullout energy of the helicoidal structure is analyzed based on the representative model of the structure. The result shows that the pullout energy of the helicoidal structure is markedly larger than that of the conventional 0 o -structure. A biomimetic composite with the observed helicoidal structure is designed and fabricated. A comparative test shows that the fracture toughness of the biomimetic composite is markedly larger than that of the 0 o -layer composite

  5. METHODS FOR THE REPRESENTATION OF THE HELICOIDAL SURFACE

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    SCURTU Liviu-Iacob

    2017-05-01

    Full Text Available In this paper there are presented the graphical methods to determine the parameters of an helicoidal stairs. The first part of this paper shows the used methods to generate the helicoidal curves using descriptive geometry methods. It has represented the state of the art of the generation of a helical surface studies. The second part of this study shows the helical stairs surface representation using descriptive geometry methods. For the representation of the helicoidal stairs are used two projections, the front and top view. A method of the stairs representation is solved using CAD modelling dedicated software. Following the helical surface representation in both methods, has been achieved a comparative study by using two representation methods. Conclusions about these two representation methods are presented in the end of this paper.

  6. In vivo thermoluminescent dosimetry in studies of helicoid computed tomography and excretory urogram; Dosimetria termoluminiscente In vivo en estudios de tomografia computada helicoidal y urograma excretor

    Energy Technology Data Exchange (ETDEWEB)

    Cruz C, D.; Azorin N, J. [UAM-I, 09340 Mexico D.F. (Mexico); Saucedo A, V.M.; Barajas O, J.L. [Unidad de Especialidades Medicas, Secretaria de la Defensa Nacional, 11500 Mexico D.F. (Mexico)

    2005-07-01

    The dosimetry is the field of measurement of the ionizing radiations. It final objective is to determine the 'absorbed dose' for people. The dosimetry is vital in the radiotherapy, the radiological protection and the treatment technologies by irradiation. Presently work, we develop 'In vivo' dosimetry, in exposed patients to studies of helical computed tomography and excretory urogram. The dosimetry 'in vivo' was carried out in 20 patients selected aleatorily, for each medical study. The absorbed dose was measured in points of interest located in crystalline, thyroid, chest and abdomen of each patient, by means of thermoluminescent dosemeters (TLD) LiF: Mg,Cu,P + Ptfe of national fabrication. Also it was quantified the dose in the working area. (Author)

  7. Helicoid peripapillary chorioretinal degeneration complicated by choroidal neovascularization.

    Science.gov (United States)

    Triantafylla, Magdalini; Panos, Georgios D; Dardabounis, Doukas; Nanos, Panagiotis; Konstantinidis, Aristeidis

    2016-02-15

    Helicoid peripapillary chorioretinal degeneration (HPCD) is a hereditary disease of the fundus that is characterized by atrophic chorioretinal areas that appear early in life and expand gradually from the optic disc towards the macula and the periphery. We describe the case of an elderly man with a known diagnosis of HPCD who developed choroidal neovascular membrane (CNV) in both eyes during the course of the disease. The patient was treated with intravitreal injection of ranibizumab, to which he had excellent response. The CNV subsided with 2 injections in the right eye and 1 in the left. Two years after the initial diagnosis of CNV in the right eye, visual acuity was 5/10 OD and 9/10 OS. Helicoid peripapillary chorioretinal degeneration is rarely complicated by CNV as the fundus lacks the trigger factors that would sustain this process. Although rare, HPCD complicated by CNV can be seen bilaterally, but responds well to few ranibizumab injections.

  8. Criptococose pulmonar: aspectos na tomografia computadorizada

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    Silva Ana Carina Gamboa da

    2003-01-01

    Full Text Available A criptococose pulmonar é uma doença causada pelo Criptococcus neoformans, um fungo unimórfico que possui distribuição mundial, existindo na mesma forma tanto no seu habitat natural quanto em animais e humanos. A doença possui apresentações clínica e patológica variáveis e pode manifestar-se tanto em pacientes com a imunidade normal como em imunocomprometidos, que representam a maioria dos casos. Neste trabalho são analisados os aspectos encontrados nas tomografias computadorizadas do tórax de 14 pacientes com criptococose pulmonar confirmada. Os achados mais freqüentes na tomografia do tórax foram as massas e os nódulos pulmonares. Outros aspectos observados foram as áreas de escavação, as consolidações, o espessamento do interstício peribroncovascular e o reticulado difuso. Massa pulmonar foi o achado isolado mais comum (64,2%, seguido dos nódulos isolados ou múltiplos (35,7%. Doença pulmonar difusa foi vista em apenas 14,2% dos casos. Os lobos superiores foram os mais comprometidos, sendo a doença mais comum nas regiões anteriores. A tomografia do tórax permitiu avaliar com precisão o grau de comprometimento do parênquima pulmonar.

  9. Reinforced concrete tomography; Tomografia de hormigon armado

    Energy Technology Data Exchange (ETDEWEB)

    Mariscotti, M A.J.; Morixe, M; Tarela, P A; Thieberger, P [Tomografia de Hormigon Armado S.A., Boulogne (Argentina)

    1998-12-31

    In this paper we describe the technique of reinforced concrete tomography, its historical background, recent technological developments and main applications. Gamma radiation sensitive plates are imprinted with radiation going through the concrete sample under study, and then processed to reveal the presence of reinforcement and defects in the material density. The three dimensional reconstruction, or tomography, of the reinforcement out of a single gammagraphy is an original development alternative to conventional methods. Re-bar diameters and positions may be determined with an accuracy of {+-} 1 mm 0.5-1 cm, respectively. The non-destructive character of this technique makes it particularly attractive in cases of inhabited buildings and diagnoses of balconies. (author) 8 refs., 12 figs. [Espanol] En este trabajo se describe la tecnica de tomografia de hormigon armado, sus antededentes, recientes desarrollos y aplicaciones mas importantes. Esta tecnica se basa en el uso de radiacion gamma para penetrar piezas de hormigon. Placas gammagraficas son sensibilizadas con la radiacion que atraviesa la pieza bajo estudio y luego procesadas para revelar la presencia de armadura e inhomogeneidades en la densidad del concreto. La reconstruccion tridimensional o tomografia, de la armadura a partir de una sola gammagrafia es un desarrollo original alternativo a los metodos convencionales. Diametros y posiciones de los hierros existentes en el interior de columnas, vigas y losas pueden ser determinados con precisiones de {+-} 1 mm y 0.5-1 cm, respectivamente. La condicion de no destructiva hace que esta tecnica sea particularmente apreciada en los casos de edificios habitados y sea insustituible para el diagnostico de balcones. (autor)

  10. First report of root rot caused by Phytopythium helicoides on pistachio rootstock in California

    Science.gov (United States)

    We examined pathogenicity of Phytopythium helicoides on UCB-1 rootstock to investigate its role in root disease and collapse observed on potted pistachio plants. Approximately 25 potted 2-year-old pistachio rootstock trees in a Kern County, CA, research plot maintained outdoors and irrigated to cont...

  11. Pulmonary artery aneurysm in Bechcet's disease: helical computed tomography study; Aneurisma de la arteria pulmonar en la enfermedad de Behcet. Estudio con tomografia computarizada helicoidal

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, J.; Caballero, P.; Olivera, M. J.; Cajal, M. L.; Caniego, J. L. [Hospital de la Princesa. Iniversidad Autonoma. Madrid (Spain)

    2000-07-01

    Behcet's disease is a vasculitis of unknown etiology that affects arteries and veins of different sizes and can be associated with pulmonary artery aneurysms. We report the case of a patient with Behcet's disease and a pulmonary artery aneurysm who was studied by means of plain chest X ray, helical computed tomography and pulmonary arteriography. Helical computed tomography is a reliable technique for the diagnosis and follow-up of these patients. (Author) 9 refs.

  12. Tomografia computadorizada no diagnóstico da otosclerose fenestral

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    Vicente Andy de Oliveira

    2004-01-01

    Full Text Available OBJETIVO: Identificar os principais achados tomográficos da otosclerose fenestral e avaliar a utilidade da tomografia computadorizada de alta resolução (TCAR, como método diagnóstico dessa osteodistrofia. FORMA DE ESTUDO: Estudo prospectivo multicêntrico com tomografia computadorizada (TC de ossos temporais. MATERIAL E MÉTODO: 54 pacientes com diagnóstico clínico e cirúrgico de otosclerose. Foi realizada uma análise tomográfica, em que foi avaliada a sensibilidade da TC no diagnóstico radiológico da otosclerose fenestral, sendo verificados os principais sítios de lesões dessa doença, como também a sua bilateralidade e simetria. Foram incluídos neste estudo 22 pacientes submetidos à TC de ossos temporais para investigação de outras afecções otológicas, que constituíram o grupo controle. RESULTADOS: A TC foi positiva em 87% dos pacientes (77% das orelhas. Os achados tomográficos foram bilaterais na maioria dos casos (78,7%, e o foco fenestral mais prevalente foi o foco anterior à janela oval (FAJO. CONCLUSÕES: A TC apresentou um alto índice de positividade e o FAJO foi o foco mais prevalente nessa população, podendo ser considerado um achado tomográfico altamente sugestivo de otosclerose.

  13. Tomografia computadorizada no seguimento de pacientes com tumores intracranianos

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    Gilberto Machado de Almeida

    1981-03-01

    Full Text Available A tomografia computadorizada tem grande valor no controle dos pacientes com tumores cerebrais. Imediatamente após o ato cirúrgico pode ser útil para avaliar a retirada do processo expansivo ou para comprovar a área atingida. Nos primeiros dias após a intervenção tem sido indicada principalmente quando há piora do quadro neurológico. Nestas condições, o exame permite verificar a existência de ar, edema, hematoma, desvios ventriculares e hidrocéfalo. Os dados fornecidos são mais precisos que os obtidos com outros exames neuror-radiológicos ou com a medida contínua da pressão intracraniana, métodos menos inócuos. A longo prazo a tomografia permite o diagnóstico precoce de recidivas, a avaliação da eficácia de tratamentos radio ou quimioterápicos e o controle do hidrocéfalo. Ainda não é possível fazer o diagnóstico diferencial entre radio-necrose e recidiva tumoral.

  14. Experimental analysis of the velocity field in an anular channel with helicoidal wire

    International Nuclear Information System (INIS)

    Lemos, M.J.S. de.

    1979-06-01

    In general, nuclear reactor fuel elements are rod bundles with coolant flowing axially among them. LMFBR's (Liquid Metal Fast Breeder Reactor) have wire wrapped fuel rods, with the wire working as spacer and mixer. The present work consists in the experimental analysis of the velocity field created by a typical LMFBR fuel rod placed in a cylinder, yielding an annular channel with helicoidal wire. Using hot wire anemometry, the main and secondary velocity fields were measured. The range for Re was from 2.2x 10 4 to 6.1x 10 4 , for air. The aspect ratio, P/D, and the lead-to-diameter ratio, 1/D, were 1.2 and 15, respectively. (Author) [pt

  15. Continuous transesterification of biodiesel in a helicoidal reactor using recycled oil

    International Nuclear Information System (INIS)

    Avellaneda, Fredy; Salvado, Joan

    2011-01-01

    The main problem with biodiesel is the high cost of oils made from oleaginous crops. For this reason, various raw materials have been analysed with a view to reducing production costs and obtaining a product that can compete with the price of petrodiesel. Recycled oil is one of the most promising alternatives in the production of biodiesel because not only is the cheapest raw material but it also avoids the expense of treating the oil as a residue. Another way to reduce costs is to make the process more economical. Conventional technology uses sodium hydroxide as the basic catalyst and large-scale batch reactors, whose mechanical agitation requires high energy consumption due to residence times of at least 60 min and temperatures of 60 C. In this paper we use a recycled pretreated oil to compare conventional transesterification with continuous transesterification in a tubular reactor. In this reactor the reactants (oil, methanol and sodium hydroxide) flow through a helicoidal tube submerged in a heating bath at 60 C. The reactor has five outlets distributed non-uniformly to enable samples to be taken at different reaction times. This is to reduce the reaction time and avoid the need for mechanical agitation. With the aim of improving the quality of the biodiesel obtained, we varied the helicoidal system by incorporating a static micromixer and supplying energy in the form of ultrasound from the heating bath. This reactor produced biodiesel and glycerine at compositions roughly equal to those obtained in the batch process (89% FAME content at 75 min) but did so continuously (2.5 mL/min) and just 13 min after the reactants were integrated in a single line using a T device. Both the oil and the biodiesel were characterized and analysed in accordance with European standard UNE EN14214 for biodiesel. (author)

  16. The Borromini's helicoidal staircase in Barberini Palace: scan laser survey and parametric modeling.

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    Leonardo Paris

    2015-07-01

    Full Text Available The paper concerns the study of the shape and geometry of the helicoidal staircase in Barberini Palace. Integrated models of representation (graphic and 3D have been produced starting from the digital data acquired by a laser scanner, processed and subsequently managed through procedures for optimizing the cloud-points.The realization of the helicoidal staircase in the Barberini Palace has an important rule in the architectural history because  it is a wonderful example of the constructive development of a complex geometric shape which is a helix oval. This stair should be read and interpreted as evidence of a particular period,the Roman Baroque, rich of intertwining and overlapping of ecclesiastical and noble commissions, of alternations in the yards of the greatest artists and architects of the era, often working simultaneously. Borromini proposes a modification to the first design of Maderno, which included a helicoidal staircase to the right of the large porch entrance to the palace, imagining a new oval stair  with a set of six twin columns for each revolution, very similar to the staircase that had been built a few years earlier, in 1585, at the Quirinale Palace by the Mascherino. Borromini had worked a few years earlier, under the direction of Maderno, in the Quirinal Palace, having a possibility to carefully study the Mascherino’s oval stair .Following the death of Maderno (1629 the yard of the Barberini Palace takes over the Bernini. Borromini will initiate a collaboration destined to end soon. The scale will be built in 1633 when now Borromini had already left the yard.The article wants above all to highlight the correlations between form and geometry when designing a campaign of digital acquisition using a laser scanner. Indeed, there are important implications to choice the positioning points of the instrument, with important fallout on the relationship between quality and quantity of a points cloud. The points cloud is a 3D

  17. Biópsia mamária realizada pela técnica de biópsia helicoide: estudo experimental Breast biopsy performed by the helicoid biopsy technique: an experimental study

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    Eliel de Souza

    2010-12-01

    Full Text Available OBJETIVO: avaliar o desempenho da biópsia helicoide na realização de biópsias mamárias. MÉTODOS: foi selecionado aleatoriamente uma amostra composta de 30 pacientes portadoras de câncer de mama submetidas à mastectomia. Foram excluídas as mulheres portadoras de tumor que tivessem consistência pétrea, não-palpável, com manipulação cirúrgica prévia ou que contivesse líquido. Utilizando-se o kit de biópsia helicoide e um equipamento de core biopsy com cânula e agulha de 14 gauge, respectivamente, coletou-se um fragmento por equipamento em área sã e nos tumores, em cada peça cirúrgica, totalizando 120 fragmentos para estudo histológico. Para a análise dos dados, definiu-se um nível de confiança de 95% e utilizou-se o software SPSS, versão 13; o índice de concordância Kappa e o teste paramétrico t de Student. RESULTADOS: a média das idades das pacientes foi de 51,6 anos (±11,1 anos. A core biopsy apresentou sensibilidade de 93,3%, especificidade de 100% e acurácia de 96,7%, enquanto a biópsia helicoide teve sensibilidade de 96,7%, especificidade de 100% e acurácia de 98,3%. Na comparação entre a histologia dos tumores e dos fragmentos de biópsias, houve alto grau de concordância nos diagnósticos (Kappa igual a 0,9, com pPURPOSE: to assess the helicoid biopsy performance when carrying out breast biopsies. METHODS: thirty patients with breast cancer submitted to mastectomy were selected at random. Women with a tumor of petreous consistency, nonpalpable, submitted to previous surgical manipulation or containing fluid were excluded. The helicoid biopsy kit and a core biopsy device with a cannula and a 14-gauge-needle, respectively, were used to collect a fragment each from a healthy area and from the tumor of each surgical specimen, for a total of 120 fragments for histological study. Data were analyzed statistically by the parametric Student's t-test and by the Kappa concordance index at the 95% confidence level

  18. Monte Carlo analysis of thermal transpiration effects in capacitance diaphragm gauges with helicoidal baffle system

    International Nuclear Information System (INIS)

    Vargas, M; Stefanov, S; Wüest, M

    2012-01-01

    The Capacitance Diaphragm Gauge (CDG) is one of the most widely used vacuum gauges in low and middle vacuum ranges. This device consists basically of a very thin ceramic or metal diaphragm which forms one of the electrodes of a cap acitor. The pressure is determined by measuring the variation in the capacitance due to the deflection of the diaphragm caused by the pressure difference established across the membrane. In order to minimize zero drift, some CDGs are operated keeping the sensor at a higher temperature. This difference in the temperature between the sensor and the vacuum chamber makes the behaviour of the gauge non-linear due to thermal transpiration effects. This effect becomes more significant when we move from the transitional flow to the free molecular regime. Besides, CDGs may incorporate different baffle systems to avoid the condensation on the membrane or its contamination. In this work, the thermal transpiration effect on the behaviour of a rarefied gas and on the measurements in a CDG with a helicoidal baffle system is investigated by using the Direct Simulation Monte Carlo method (DSMC). The study covers the behaviour of the system under the whole range of rarefaction, from the continuum up to the free molecular limit and the results are compared with empirical results. Moreover, the influence of the boundary conditions on the thermal transpiration effects is investigated by using Maxwell boundary conditions.

  19. Modulational instability and discrete breathers in a nonlinear helicoidal lattice model

    Science.gov (United States)

    Ding, Jinmin; Wu, Tianle; Chang, Xia; Tang, Bing

    2018-06-01

    We investigate the problem on the discrete modulation instability of plane waves and discrete breather modes in a nonlinear helicoidal lattice model, which is described by a discrete nonlinear Schrödinger equation with the first-, second-, and third-neighbor coupling. By means of the linear stability analysis, we present an analytical expression of the instability growth rate and identify the regions of modulational instability of plane waves. It is shown that the introduction of the third-neighbor coupling will affect the shape of the areas of modulational instability significantly. Based on the results obtained by the modulational instability analysis, we predict the existence conditions for the stationary breather modes. Otherwise, by making use of the semidiscrete multiple-scale method, we obtain analytical solutions of discrete breather modes and analyze their properties for different types of nonlinearities. Our results show that the discrete breathers obtained are stable for a long time only when the system exhibits the repulsive nonlinearity. In addition, it is found that the existence of the stable bright discrete breather closely relates to the presence of the third-neighbor coupling.

  20. Tomografia computadorizada das patologias acometendo o compartimento iliopsoas

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    Montandon Cristiano

    2001-01-01

    Full Text Available Este trabalho tem como objetivo revisar as patologias que acometem o compartimento iliopsoas. Foi realizada análise retrospectiva de casos com acometimento do compartimento iliopsoas avaliados por tomografia computadorizada (TC, no Departamento de Radiologia da Faculdade de Ciências Médicas da Universidade Estadual de Campinas, nos últimos dez anos, confirmados por biópsia cirúrgica ou percutânea. Os principais diagnósticos encontrados foram neoplasias, abscessos e hematomas. Os achados tomográficos baseiam-se na extensão do acometimento iliopsoas, no grau de atenuação, margens da lesão, presença de gás e/ou calcificações, destruição óssea, infiltração da gordura e acometimento de estruturas abdominais adjacentes. A TC é o método de escolha na avaliação do compartimento iliopsoas, podendo ser utilizada para orientar biópsias percutâneas, cirúrgicas ou drenagem. Porém, os achados isolados do estudo por TC, sem o conhecimento da história clínica, não são específicos para permitir a diferenciação das diversas patologias que acometem o compartimento iliopsoas.

  1. Lesões traumáticas do parênquima pulmonar: aspectos na tomografia computadorizada Traumatic lung lesions: computed tomography findings

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    Alessandro Severo Alves de Melo

    2003-06-01

    Full Text Available As lesões pulmonares são achados freqüentes no trauma torácico, sendo cada vez mais diagnosticadas pela tomografia computadorizada, em especial pelo rápido tempo de aquisição decorrente da técnica helicoidal, que permite a avaliação de pacientes em estado grave, possibilitando a adoção de conduta terapêutica eficiente. Os autores estudaram 150 pacientes vítimas de trauma torácico submetidos a tomografia computadorizada, que apresentaram lesões pulmonares, representadas por contusões, atelectasias, lacerações e hematomas pulmonares. As contusões pulmonares se caracterizaram por consolidações e atenuação em vidro fosco, sendo as lesões pulmonares mais comuns. As atelectasias foram observadas com os padrões subsegmentar e compressiva, e foram a segunda lesão mais comum. As lacerações se apresentaram como consolidações com ar ou nível líquido no interior. Os hematomas pulmonares representaram a lesão pulmonar mais rara, presentes em apenas cinco casos, caracterizados por opacidades arredondadas. Neste trabalho o trauma torácico fechado predominou, com 120 casos, enquanto o trauma aberto ocorreu em 30 casos. As causas de trauma fechado, em ordem decrescente de freqüência, foram: colisão automobilística, atropelamento, queda de altura, acidente de motocicleta e espancamento. A forma penetrante de traumatismo torácico decorreu de duas causas de agressão: lesão por arma de fogo e lesão por arma branca.Traumatic lesions of the lung are common findings in patients with thoracic trauma. These lesions are increasingly diagnosed using computed tomography, mostly due to the fast acquisition time helical techniques that allow evaluation of critically ill patients and an efficient therapeutic management. The authors studied 150 patients with thoracic trauma submitted to computed tomography that demonstrated lung contusions, atelectasies, lacerations and hematomas. Lung contusions were the most frequent lesions

  2. Development of SCAR markers and PCR assays for single or simultaneous species-specific detection of Phytophthora nicotianae and Pythium helicoides in ebb-and-flow irrigated kalanchoe.

    Science.gov (United States)

    Ahonsi, Monday O; Ling, Yin; Kageyama, Koji

    2010-11-01

    Phytophthora nicotianae and Pythium helicoides are important water-borne oomycete pathogens of irrigated ornamentals particularly ebb-and-flow irrigated kalanchoe in Japan. We developed novel PCR-based sequence characterized amplified region markers and assays for rapid identification and species-specific detection of both pathogens in separate PCR reactions or simultaneously in a duplex PCR.

  3. Tomografia computadorizada aplicada a estudos de um Planossolo

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    Pedrotti Alceu

    2003-01-01

    Full Text Available Na busca de técnicas mais apuradas para a determinação e avaliação de parâmetros físicos do solo com aplicabilidade em várzeas, vem se destacando a tomografia computadorizada, por medir a densidade e a umidade com boa sensibilidade e alta resolução espacial. O presente trabalho teve como objetivo descrever aspectos e procedimentos da calibração de um minitomógrafo de raios-X e gama para estudo da densidade e umidade de um Planossolo no Rio Grande do Sul, bem como estabelecer parâmetros estatísticos para sua adequada utilização. A calibração do minitomógrafo foi obtida pela regressão linear entre as unidades tomográficas (UT, apresentadas pelo programa de reconstrução de imagem, e os coeficientes de atenuação linear (µl, cm-1, medidos por transmissão direta de raios gama, em amostras dos horizontes A e B do Planossolo, água destilada, benzina e alumínio. Para as medidas de transmissão direta de radiação utilizaram-se recipientes com água destilada, benzina, solo e Al, obtendo-se as seguintes fórmulas para o cálculo da densidade do solo no horizonte A: Ds = [(UT/986,16-(0,200xteta]/0,267; e no horizonte B: Ds = [(UT/986,16-(0,200xteta]/0,297, em que UT é o valor médio de UT em cada linha e teta é a umidade volumétrica da amostra de solo, em m³ m-3. Com as configurações obtidas, verificou-se variabilidade média de 2,74% e 0,73%, respectivamente, em termos de homogeneidade e repetibilidade. Os erros atribuídos ao equipamento são de 0,051 e 0,046 Mg m-3, respectivamente, nos horizontes A e B, revelando precisão e adaptabilidade no emprego da técnica em estudos do Planossolo.

  4. Avaliação da concordância interobservador na análise da tomografia computadorizada sem contraste no diagnóstico da urolitíase em pacientes com cólica renal aguda Interobserver agreement on non-contrast computed tomography interpretation for diagnosis of urolithiasis in patients with acute flank pain

    Directory of Open Access Journals (Sweden)

    Luís Ronan Marquez Ferreira de Souza

    2006-10-01

    Full Text Available OBJETIVO: Avaliar a reprodutibilidade da tomografia computadorizada sem contraste na avaliação da litíase ureteral e os sinais secundários de obstrução do sistema coletor em pacientes com cólica renal aguda. MATERIAIS E MÉTODOS: Estudo prospectivo de 52 pacientes com diagnóstico clínico de cólica renal aguda submetidos a exame de tomografia computadorizada de abdome sem contraste. Os exames foram realizados com técnica helicoidal e posteriormente analisados por três observadores independentes, com a concordância interobservador avaliada pelo método estatístico kappa (kapa. Foram analisados os parâmetros: a presença, localização e mensuração dos cálculos ureterais; b dilatação do sistema coletor intra-renal; c heterogeneidade da gordura perirrenal; d dilatação ureteral; e edema da parede ureteral (sinal do halo. RESULTADOS: Foram encontrados 40 cálculos ureterais na tomografia computadorizada (77%. A concordância interobservador para a identificação do cálculo ureteral e da dilatação ureteral foi quase perfeita (kapa = 0,89 e kapa = 0,87, respectivamente, substancial para dilatação do sistema coletor intra-renal (kapa = 0,77 e moderada para heterogeneidade da gordura perirrenal e para edema da parede ureteral (kapa = 0,55 e kapa = 0,56, respectivamente. CONCLUSÃO: A tomografia computadorizada de abdome sem contraste apresenta elevada reprodutibilidade na avaliação da litíase ureteral e dos sinais secundários de obstrução do sistema coletor.OBJECTIVE: To evaluate the interobserver agreement on non-contrast computed tomography interpretation by a group of experienced abdominal radiologists, for the study of urolithiasis in patients presenting acute flank pain. MATERIALS AND METHODS: Prospective study of 52 patients submitted to non-contrast enhanced helical computed tomography. The images were subsequently analyzed by three independent observers, with the interobserver agreement assessed by means of the

  5. Towards chiral distributions of dopants in microporous frameworks: helicoidal supramolecular arrangement of (1R,2S)-ephedrine and transfer of chirality.

    Science.gov (United States)

    Gómez-Hortigüela, Luis; Álvaro-Muñoz, Teresa; Bernardo-Maestro, Beatriz; Pérez-Pariente, Joaquín

    2015-01-07

    A molecular-mechanics computational study is performed in order to analyze the arrangement of (1R,2S)-(-)-ephedrine molecules within the 12-MR channels of the AFI aluminophosphate microporous framework and the influence on the spatial distribution of dopants embedded in the tetrahedral network. Results showed that ephedrine molecules arrange exclusively as dimers by π-π stacking of the aromatic rings within the AFI channels. Interestingly, the asymmetric nature of ephedrine and the presence of H-bond-forming groups (NH2 and OH) involve a preferential orientation where consecutive dimers within the channels are rotated by an angle of +30°; this is driven by the establishment of inter-dimer H-bonds. This preferential orientation leads to the development of a supramolecular enantiomerically-pure helicoidal (chiral) arrangement of ephedrine dimers. In addition, the computational results demonstrate that the particular molecular structure of ephedrine imparts a strong trend to attract negative charges to the vicinity of the NH2(+) positively-charged groups. Hence divalent dopants such as Mg, whose replacement by trivalent Al in the aluminophosphate network involves the generation of a negative charge, will tend to locate close to the NH2(+) molecular groups, suggesting that an imprinting of the organic arrangement to the spatial distribution of dopants would be feasible. Combined with the trend of ephedrine to arrange in a helicoidal fashion, an enantiomerically-pure helicoidal distribution of dopants would be expected, thus inducing a new type of chirality in microporous materials.

  6. Densitometria da vértebra dorsal, osso pleural e osso neural em tartarugas verdes hígidas por tomografia computadorizada quantitativa Densitometry of dorsal vertebrae, pleural bone and neural bone in healthy green sea turtles by quantitative computed tomography

    Directory of Open Access Journals (Sweden)

    Jannine Forattini de Oliveira

    2012-08-01

    Full Text Available A tomografia computadorizada quantitativa (TCQ é uma técnica com alta sensibilidade, aplicabilidade e precisão no diagnóstico de perda de massa óssea, entretanto a falta de valores de normalidade para animais silvestres limita a sua aplicação clínica. O presente estudo objetiva estabelecer valores médios de radiodensidade do osso trabecular das vértebras dorsais, osso pleural e osso neural de tartarugas marinhas juvenis hígidas utilizando a TCQ. Para isso, utilizou-se um grupo experimental de cinco animais que foram submetidos a exames de tomografia computadorizada helicoidal, sendo as mensurações da radiodensidade óssea realizadas ao nível da terceira, quarta e quinta vértebras dorsais. Os valores médios de radiodensidade do osso trabecular das vértebras dorsais, osso pleural e osso neural foram, respectivamente, de 287,4±39,1, 1093,74±100,4 e 1089,6±86,5 unidades Hounsfield (HU. Estudos complementares devem ser realizados em diferentes espécies e faixas etárias de quelônios para favorecer a aplicação clínica desta técnica.Quantitative computed tomography (QCT is a technique with high sensitivity, applicability and accuracy in the diagnosis of bone loss; however the lack of normal values for wild animals limits their clinical application. This study aims to establish medium values radiodensity trabecular bone of the dorsal vertebrae, bone pleural and neural bone in healthy juvenile sea turtles using the QTC. For this we used an experimental group of five animals that underwent helical computed tomography, and measurements of bone radiodensity conducted at the level of the third, fourth and fifth dorsal vertebrae. The medium values of radiodensity trabecular bone of the dorsal vertebrae, pleural bone, and neural bone were respectively 287.4±39.1, 1093.74±100.4, and 1089.6±86.5 Hounsfield units (HU. Further studies should be performed in different species and ages of turtles to encourage the clinical application of

  7. Mudanças na estrutura do solo avaliada com uso de tomografia computadorizada.

    OpenAIRE

    PIRES, L. F.; BACCHI, O. O. S.

    2010-01-01

    O objetivo deste trabalho foi avaliar, em escala milimétrica, a modificação da densidade e da porosidade de amostras deformadas de solo submetidas a ciclos de umedecimento e secamento (U-S), por meio da tomografia computadorizada de raios gama. Amostras com 98,1 cm³ foram preparadas procedendo ao peneiramento do solo em malha de 2 mm e acondicionamento de forma homogênea em tubos de PVC. As amostras de solo foram submetidas a um, dois e três ciclos de U-S. As amostras controle não foram subme...

  8. Alterações no planejamento em implantodontia utilizando a tomografia computadorizada volumétrica

    OpenAIRE

    Pedroso, Ludmila Assunção de Mello

    2011-01-01

    O sucesso da reabilitação sobre implantes depende de um planejamento bem executado. Nesta fase, as características do sítio e as estruturas anatômicas adjacentes são avaliadas por meio do exame clínico e dos exames por imagem. A radiografia panorâmica é amplamente utilizada, mas recomenda-se que uma imagem seccional seja realizada. A tomografia computadorizada volumétrica (TCV) está entre os exames com maior indicação para essa avaliação. O objetivo deste trabalho foi verifi...

  9. Avaliação da expansão rápida da maxila por meio da tomografia computadorizada: relato de um caso Computed tomography evaluation of rapid maxillary expansion: a case report

    Directory of Open Access Journals (Sweden)

    Daniela Gamba Garib

    2005-08-01

    Full Text Available Este trabalho descreve os efeitos dentoesqueléticos e periodontais da expansão rápida da maxila (ERM, avaliados por meio da tomografia computadorizada (TC, em uma jovem de 11,6 anos de idade com má oclusão de Classe I e mordida cruzada posterior unilateral funcional. Durante a fase ativa da ERM, o expansor dentossuportado com parafuso Hyrax foi ativado 7mm. A paciente submeteu-se ao exame de TC helicoidal, antes da expansão e após a remoção do aparelho expansor, findo o período de três meses de contenção. Realizaram-se cortes axiais, de um milímetro de espessura, paralelamente ao plano palatino, englobando as regiões dentoalveolar e basal da maxila, até o terço inferior da cavidade nasal. Utilizando-se o recurso de reconstruções multiplanares, mensuraram-se pelo método computadorizado: as dimensões transversas maxilares, a inclinação dos dentes posteriores, a espessura das tábuas ósseas vestibular e lingual, e o nível da crista óssea alveolar vestibular. A expansão rápida da maaxila ocasionou um significante aumento transverso em todas as regiões aferidas, com magnitude decrescente do arco dentário para a base óssea. Os dentes posteriores foram movimentados para vestibular, com um componente de inclinação e translação associados. Tal efeito ortodôntico ocasionou uma redução na espessura da tábua óssea vestibular, e um concomitante aumento na espessura da tábua óssea lingual. Após a expansão, observou-se o desenvolvimento de deiscências ósseas por vestibular dos dentes de ancoragem.This paper presents a computed tomography (CT evaluation of rapid maxillary expansion dentoskeletal and periodontal effects, in a 11.6 year-old girl presenting Class I malocclusion with posterior unilateral crossbite. The tooth-borne expander with Hyrax screw was activated 7-mm. The patient was submitted to helicoidal CT scan before expansion and after the three-month retention period when the expander was removed. Axial

  10. HELICoiD project: a new use of hyperspectral imaging for brain cancer detection in real-time during neurosurgical operations

    Science.gov (United States)

    Fabelo, Himar; Ortega, Samuel; Kabwama, Silvester; Callico, Gustavo M.; Bulters, Diederik; Szolna, Adam; Pineiro, Juan F.; Sarmiento, Roberto

    2016-05-01

    Hyperspectral images allow obtaining large amounts of information about the surface of the scene that is captured by the sensor. Using this information and a set of complex classification algorithms is possible to determine which material or substance is located in each pixel. The HELICoiD (HypErspectraL Imaging Cancer Detection) project is a European FET project that has the goal to develop a demonstrator capable to discriminate, with high precision, between normal and tumour tissues, operating in real-time, during neurosurgical operations. This demonstrator could help the neurosurgeons in the process of brain tumour resection, avoiding the excessive extraction of normal tissue and unintentionally leaving small remnants of tumour. Such precise delimitation of the tumour boundaries will improve the results of the surgery. The HELICoiD demonstrator is composed of two hyperspectral cameras obtained from Headwall. The first one in the spectral range from 400 to 1000 nm (visible and near infrared) and the second one in the spectral range from 900 to 1700 nm (near infrared). The demonstrator also includes an illumination system that covers the spectral range from 400 nm to 2200 nm. A data processing unit is in charge of managing all the parts of the demonstrator, and a high performance platform aims to accelerate the hyperspectral image classification process. Each one of these elements is installed in a customized structure specially designed for surgical environments. Preliminary results of the classification algorithms offer high accuracy (over 95%) in the discrimination between normal and tumour tissues.

  11. Chlorella vulgaris as a lipid source: Cultivation on air and seawater-simulating medium in a helicoidal photobioreactor.

    Science.gov (United States)

    Frumento, Davide; Aliakbarian, Bahar; Casazza, Alessandro Alberto; Converti, Attilio; Al Arni, Saleh; da Silva, Milena Fernandes

    2016-03-01

    The freshwater microalga Chlorella vulgaris was cultured batchwise on the seawater-simulating Schlösser medium either in a 1.1-L-working volume helicoidal photobioreactor (HeP) or Erlenmeyer flask (EF) as control and continuously supplying air as CO2 source. In these systems, maximum biomass concentration reached 1.65 ± 0.17 g L(-1) and 1.25 ± 0.06 g L(-1) , and maximum cell productivity 197.6 ± 20.4 mg L(-1)  day(-1) and 160.8 ± 12.2 mg L(-1)  day(-1) , respectively. Compared to the Bold's Basal medium, commonly employed to cultivate this microorganism on a bench-scale, the Schlösser medium ensured significant increases in all the growth parameters, namely maximum cell concentration (268% in EF and 126% in HeP), maximum biomass productivity (554% in EF and 72% in HeP), average specific growth rate (67% in EF and 42% in HeP), and maximum specific growth rate (233% in EF and 22% in HeP). The lipid fraction of biomass collected at the end of runs was analyzed in terms of both lipid content and fatty acid profile. It was found that the seawater-simulating medium, despite of a 56-63% reduction of the overall biomass lipid content compared to the Bold's Basal one, led in HeP to significant increases in both the glycerides-to-total lipid ratio and polyunsaturated fatty acid content compared to the other conditions taken as an average. These results as a whole suggest that the HeP configuration could be a successful alternative to the present means to cultivate C. vulgaris as a lipid source. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:279-284, 2016. © 2016 American Institute of Chemical Engineers.

  12. Tomografia computadorizada do cranio no diagnostico dos meningiomas: registro de 16 casos

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    James Pitagoras de Mattos

    1983-03-01

    Full Text Available Os autores se referem à importância do emprego da tomografia computadorizada do crânio para o preciso diagnóstico dos meningiomas. Constam da experiência 16 casos, comprovados cirúrgica e histologicamente. A média de idade foi de 52,1 anos, sendo 10 pacientes do sexo feminino e 6 do masculino. Quanto à localização, 5 eram da cavidade orbitrária e/ou asa do esfenóide, 3 parasagitais, 3 da foice, 2 supra-selares, 2 de convexidade e 1 do tentório. Concluem tratar-se de exame de grande positividade (95-98%, praticamente inócuo e que permite, na atualidade, o diagnóstico precoce conduzindo, consequentemente, a melhores resultados terapêuticos.

  13. Histiocitoma fibroso benigno profundo: achados na tomografia computadorizada e histologia Deep benign fibrous histiocytoma: computed tomography and histology findings

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    Luciano Farage

    2005-04-01

    Full Text Available Apresentamos imagens de tomografia computadorizada de um paciente de 83 anos de idade com histiocitoma fibroso benigno profundo, na face lateral da perna esquerda, com evolução de longa data. À tomografia computadorizada observamos massa bem delimitada, ovalada, e que apresentava intenso realce periférico com uso do meio de contraste iodado. Este é um tumor de partes moles pouco freqüente e com raros relatos dos seus aspectos de imagem.We present the computed tomography images of an 83-year-old male patient with a deep benign fibrous histiocytoma at the lateral aspect of the left leg. Computed tomography images showed a well-defined mass with marked peripheral enhancement by iodinated contrast medium. Only few reports of this rare soft tissue tumor can be found in the literature.

  14. Study of the failure in service of a linepipe, helicoidally welded, quality API SL GrB wich conveyed natural gas. Estudio del fallo en servicio de una tuberia soldada helicoidalmente de calidad API SL SrB que transportaba gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez de Saiz-Solabarria, S.; Elices, M.A. (Departamento de Ciencias de los Materiales e Ingenieria Metalurgica, Universidad del Pais Vasco, Bilbao (Spain))

    1994-01-01

    The possible causes are studied which have incidentally provoked a failure in service on a natural gas linepipe run. This pipe has been manufactured with 6 mm-thick-plate-coil helicoidally welded to 273 mm external diameter. The quality of the material is up to standard API 5L for Grade B and an automatic-helicoidally welding procedure has been with simultaneous inflow at both internal and and external surfaces. The failure appears together with deformations and fracture. (Author)

  15. Estimativa dos valores de MSAD em procedimentos de tomografia computadorizada utilizando filmes radiocrômicos

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    Bruno Beraldo Oliveira

    2013-04-01

    Full Text Available OBJETIVO: Verificar a viabilidade de filmes radiocrômicos como um dosímetro alternativo para estimativa da dose média em cortes múltiplos a partir dos perfis de kerma. MATERIAIS E MÉTODOS: Os filmes foram distribuídos em cilindros posicionados no centro e nas regiões periféricas de um objeto simulador padrão de abdome utilizado para dosimetria em tomografia computadorizada. RESULTADOS: Os valores de dose média em cortes múltiplos calculados foram 13,6 ± 0,7, 13,5 ± 0,7 e 18,7 ± 1,0 mGy para os valores de passo (pitch de 0,75, 1,00 e 1,50, respectivamente. CONCLUSÃO: Apesar de os resultados mostrarem valores menores que o nível de referência de radiodiagnóstico de 25 mGy estabelecido pela legislação brasileira para exames de abdome, eles sugerem que há espaço para otimização dos procedimentos e uma revisão do valor para o nível de referência de radiodiagnóstico brasileiro.

  16. Trauma dos ossos temporais e suas complicações: aspectos na tomografia computadorizada

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    Ana Maria Doffémond Costa

    2013-04-01

    Full Text Available A maioria das fraturas dos ossos temporais resulta de traumas cranianos bruscos, de alta energia, estando muitas vezes relacionadas a outras fraturas cranianas ou a politraumatismo. As fraturas e os deslocamentos da cadeia ossicular, na orelha média, representam umas das principais complicações das injúrias nos ossos temporais e, por isso, serão abordadas de maneira mais profunda neste artigo. Os outros tipos de injúrias englobam as fraturas labirínticas, fístula dural, paralisia facial e extensão da linha de fratura ao canal carotídeo. A tomografia computadorizada tem papel fundamental na avaliação inicial dos pacientes politraumatizados, pois é capaz de identificar injúrias em importantes estruturas que podem causar graves complicações, como perda auditiva de condução ou neurossensorial, tonturas e disfunções do equilíbrio, fístulas perilinfáticas, paralisia do nervo facial, lesões vasculares, entre outras.

  17. Malária pulmonar: aspectos na tomografia computadorizada de alta resolução - relato de caso

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    Rodrigues Rosana

    2004-01-01

    Full Text Available Neste trabalho é relatado o caso de paciente do sexo masculino, de 38 anos de idade, que desenvolveu quadro de malária com comprometimento pulmonar. A tomografia computadorizada de alta resolução evidenciou espessamento de septos interlobulares e de bainhas peribroncovasculares, com áreas esparsas de atenuação em vidro fosco e de consolidações, além de derrame pleural bilateral, aspectos compatíveis com edema pulmonar. O paciente recebeu tratamento específico, evoluindo bem e tendo alta 11 dias após a internação.

  18. Tomografia Computadorizada de crânio em perícias criminais: uma grande aliada

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    Márcio Gleidson Ribeiro Dias

    2016-11-01

    Full Text Available O presente estudo trata-se de uma revisão descritiva da literatura sobre as principais vantagens da Tomografia Computadorizada (TC de crânio na área de Criminologia. Para a revisão literária foram utilizados artigos e dissertações recentes publicados entre 2007 e 2016, livros de imagenologia e medicina legal. A partir dos dados obtidos na revisão literária, nós realizamos uma descrição sobre a TC e sua evolução ao longo dos anos, suas vantagens e aplicações em perícias criminais. Destacamos a importância do laudo pericial, a responsabilidade do perito criminal, a fisiopatologia do trauma cranioencefálico e a sua relação com a violência urbana.Entre as vantagens da virtópsia em relação aos métodos tradicionais destacam-se a preservação do corpo, o arquivamento das imagens e a capacidade de identificação de vítimas através de imagens comparativas ante mortem e post mortem. Assim, a TC tem se tornado cada vez mais presente nas investigações criminais como uma tecnologia de baixo custo que é capaz de localizar, quantificar e evidenciar o trajeto de projéteis, auxiliando na identificação de cadáveres e causas da morte.

  19. Tomografia computadorizada das células etmoidais intra e extramurais: ensaio iconográfico

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    Fabrício Guimarães Gonçalves

    2011-10-01

    Full Text Available O desenvolvimento dos seios paranasais é um processo intricado que se inicia na vida intrauterina e termina na idade adulta. Dos seios da face, as células etmoidais são provavelmente as estruturas mais complexas e as que estão associadas com o maior número de variantes da normalidade. Variações no padrão de pneumatização das células etmoidais podem ser divididas em intra ou extramurais. Intramurais são aquelas que ao se desenvolverem mantêm contato com o labirinto etmoidal, e extramurais as que se desenvolvem isoladamente. A tomografia computadorizada é a ferramenta mais útil na avaliação de processos inflamatórios dos seios paranasais. De igual modo, ela é importante para o planejamento pré-operatório e controle pós-operatório, pois possibilita grande detalhe anatômico das estruturas normais e detecção precisa de suas variantes. Neste ensaio iconográfico os autores descrevem as principais variantes da normalidade do labirinto etmoidal e suas relações com estruturas adjacentes. Cirurgias endoscópicas para o tratamento de afecções dos seios paranasais têm-se tornado cada vez menos invasivas, o que certamente aumentará a demanda por relatórios de imagem cada vez mais ricos em detalhes desta região.

  20. Avaliação da reprodutibilidade da tomografia computadorizada no estadiamento da pancreatite aguda Reproducibility in the assessment of acute pancreatitis with computed tomography

    Directory of Open Access Journals (Sweden)

    Edison de Oliveira Freire Filho

    2007-12-01

    Full Text Available OBJETIVO: Medir a reprodutibilidade da tomografia computadorizada sem e com contraste na avaliação da gravidade da pancreatite aguda. MATERIAIS E MÉTODOS: Cinqüenta e um exames de tomografia computadorizada abdominal sem e com contraste de pacientes com pancreatite aguda foram analisados por dois radiologistas (observadores 1 e 2. Calculamos o índice morfológico pela tomografia computadorizada sem e com contraste, separadamente, e o índice de gravidade da tomografia computadorizada para pancreatite aguda. Medimos a reprodutibilidade intra- e interobservador da tomografia computadorizada através do índice kappa (kapa. RESULTADOS: Para a concordância interobservador obtivemos kapa de 0,666, 0,705, 0,648, 0,547 e 0,631 para índice morfológico sem e com contraste, presença de necrose pancreática, extensão da necrose pancreática e índice de gravidade da tomografia computadorizada, respectivamente. Para a concordância intra-observador dos observadores 1 e 2 obtivemos, respectivamente, kapa de 0,796 e 0,732 para o índice morfológico sem contraste; 0,725 e 0,802 para o índice morfológico com contraste; 0,674 e 0,849 para a presença de necrose pancreática; 0,606 e 0,770 para a extensão da necrose pancreática; e 0,801 e 0,687 para o índice de gravidade da tomografia computadorizada. CONCLUSÃO: O estadiamento da pancreatite aguda pela tomografia computadorizada por meio do índice morfológico e do índice de gravidade da tomografia computadorizada é um método bastante reprodutível. O não-uso do contraste não afeta a reprodutibilidade da tomografia computadorizada para o cálculo do índice morfológico.OBJECTIVE: To evaluate the reproducibility of unenhanced and contrast-enhanced computed tomography in the assessment of patients with acute pancreatitis. MATERIALS AND METHODS: Fifty-one unenhanced and contrast-enhanced abdominal computed tomography studies of patients with acute pancreatitis were blindly reviewed by two

  1. Cálculo de la transmisión paralela helicoidal de la caja multiplicadora de una turbina eólica

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    César Alberto Chagoyén-Méndez

    2014-01-01

    Full Text Available La caja multiplicadora de una turbina eólica es el componente de mayor complejidad mecánica y es la responsable de la mayoría de la pérdida de tiempo operacional de la turbina y del incremento de los costos. La misma no alcanza una vida proyectada de 20 años. Todos los estudios hasta el momento indican que estas fallas surgen desde el proceso de diseño. Este trabajo tuvo como objetivo demostrar algunas de las insuficiencias de las normas actuales de diseño de las cajas multiplicadoras de las turbinas eólicas, a través de la realización de una comparación de los resultados del cálculo de la transmisión paralela helicoidal de una turbina eólica de 2,5 MW, realizados por tres vías: con las normas ISO 6336:2006 Método B y AGMA 2101-D04 ( Metric Edition y mediante simulación numérica. De este análisis resulta que no existen problemas de resistencia ni de rigidez en ambas transmisiones, sin embargo la diferencia entre estos tres métodos de cálculo es considerable.

  2. Lesões traumáticas do tórax. Aspectos na tomografia computadorizada

    Directory of Open Access Journals (Sweden)

    Alessandro Severo Alves de Melo

    2004-09-01

    Full Text Available RESUMO: O trauma representa, no mundo actual, uma das principais causas de morte, e o acometimento torácico significa um importante agravamento nas vítimas de trauma multi-sistémico. Neste trabalho foram estudados os aspectos tomográficos de 200 pacientes com trauma torácico. As lesões pulmonares predominaram, tendo sido observadas em 192 casos (96%, manifestadas sob a forma de contusões em 178 casos (89%, atelectasias em 41 casos (20,5%, lacerações em 15 casos (7,5% e hematomas em 6 casos (3%. Lesões pleurais foram demonstradas em 140 casos (70%, dos quais em 121 casos (60,5% havia hemotórax e em 84 casos (42% pneumotórax. As lesões mediastínicas estiveram presentes em 28 casos (14%, com pneumomediastino em 18 (9%, hematoma mediastínico em 7 casos (3,5%, hemopericárdio em 4 (2% e lesões da aorta em 3 (1,5%. As lesões diafragmáticas foram observadas em 8 pacientes (4%. O enfisema de partes moles foi demonstrado em 36 casos (18%.REV PORT PNEUMOL 2004; X (5: 393-403 ABSTRACT: Trauma is nowadays one of the most common causes of death and traumatic thoracic lesions are important agravant to trauma patients. In this work the aspects of computed tomography from 200 cases of thoracic trauma were studied. Lung lesions predominated, found in 192 cases (96%, manifested as contusions in 178 cases (89%, atelectasis in 41 cases (20,5%, lacerations in 15 cases (7,5% and hematomas in 6 cases (3%. Pleural lesions were showed in 140 cases (70%, among them in 121 cases (60,5% there were hemothorax and in 84 cases (42%, pneumothorax. Mediastinal lesions were observed in 28 cases (14%, with pneumomediastinum in 18 cases (9%, mediastinal hematoma in 7 cases (3,5%, hemopericardium in 4 cases (2% and aortic lesions in 3 cases (1,5%. Diaphragmatic rupture was seen in 8 pacients (4%. Soft tissue emphysema was demonstrated in 36 cases (18%.REV PORT PNEUMOL 2004; X (5: 393-403 Palavras-chave: Tórax, tomografia computadorizada, trauma torácico, Key

  3. Estudo radiográfico e por tomografia computadorizada das formações orais em cães

    OpenAIRE

    Carolina de Oliveira Ghirelli

    2008-01-01

    As neoplasias orais representam a quarta neoplasia mais comum em cães. O diagnóstico por imagem das neoplasias orais é necessário para determinar a extensão do tumor e dos tecidos locais acometidos, auxiliando no prognóstico e planejamento cirúrgico. Atualmente o exame radiográfico é o método diagnóstico mais utilizado por ser mais acessível e menos oneroso, porém o grande número de estruturas no crânio e suas sobreposições dificultam adequada avaliação desta região. A tomografia computadoriz...

  4. Apendicite aguda: achados na tomografia computadorizada - ensaio iconográfico Acute appendicitis: computed tomography findings - an iconographic essay

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    Marcelo Eustáquio Montandon Júnior

    2007-06-01

    Full Text Available A apendicite aguda é a causa mais comum de dor abdominal aguda que requer intervenção cirúrgica no mundo ocidental. O diagnóstico precoce é essencial para minimizar a morbidade da doença. O uso dos métodos de imagem significou grande avanço no diagnóstico desta entidade, até então avaliada apenas com base na história clínica, exame físico e dados laboratoriais, haja vista que 20% a 33% dos pacientes apresentam sintomas atípicos. O diagnóstico é mais difícil nas crianças, nos idosos e nas mulheres em idade fértil. Os principais métodos de imagem para sua avaliação são a ultra-sonografia e a tomografia computadorizada. Os objetivos deste trabalho são: descrever a fisiopatologia da doença, comentar os principais aspectos técnicos da tomografia computadorizada, demonstrar e ilustrar os achados tomográficos e citar os principais diagnósticos diferenciais.Acute appendicitis is the most important cause of abdominal pain requiring surgical intervention in the Western world. The early diagnosis of this disease is of paramount relevance for minimizing its morbidity. Imaging methods have represented a huge progress in the diagnosis of this entity, which used to be based essentially on clinical history, physical examination and laboratory tests results, considering that 20% to 33% of patients present with atypical symptoms. Diagnostic difficulty is higher in children, the elderly, and women in childbearing age. The main imaging methods for evaluation of acute appendicitis are ultrasound and computed tomography. The present study is aimed at describing the disease physiopathology, commenting main computed tomography technical aspects, demonstrating and illustrating tomographic findings, and describing main differential diagnoses.

  5. La agresividad y las capacidades del área de matemática en estudiantes del tercero de secundaria de la institución educativa Saco Oliveros – Helicoidal Ate 2011

    OpenAIRE

    Espinoza Chaca, Carmen Ascenciona; Melissa Wendy Zárate Murga, Melissa Wendy

    2016-01-01

    La presente investigación tiene como objetivo determinar la relación que existe entre la agresividad y las capacidades del área de matemática en estudiantes del tercero de secundaria de la institución educativa Saco Oliveros – Helicoidal Ate 2011 . Para la investigación se utilizó un cuestionario para determinar el nivel de autoestima y actas de evaluación aprendizaje de los estudiantes. La muestra estuvo constituida por 109 estudiantes. Se realizaron pruebas estadísticas y ...

  6. Stratus optical coherence tomography findings in patients with retinopathy of prematurity Tomografia de coerência óptica em pacientes com retinopatia da prematuridade

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    Aline do Lago

    2007-02-01

    Full Text Available PURPOSE: To describe morphological features of the macula in patients with retinopathy of prematurity. METHODS: Twelve premature babies with retinopathy of prematurity grades I, II and III underwent dilated fundus examination and optical coherence tomography evaluation. RESULTS: In all thirteen eyes of the twelve premature patients optical coherence tomography revealed a condensed retinal pigmented epithelial layer in the macular-foveal area shown by increased reflectivity. In these eyes the retinal layers were not well differentiated. Foveal depression was clearly evident in 23%. CONCLUSIONS: In premature patients with retinopathy of prematurity, optical coherence tomography revealed poorly differentiated layers in the macular region with increased reflectivity in retinal pigmented epithelial-choriocapillaris zone.OBJETIVO: Descrever os aspectos morfológicos da mácula em pacientes com retinopatia da prematuridade (ROP. MÉTODOS: Doze pacientes com retinopatia da prematuridade graus I, II and III foram submetidos a mapeamento de retina e avaliação por tomografia de coerência óptica. RESULTADOS: Em todos os treze olhos de 12 pacientes a tomografia de coerência óptica mostrou a camada do epitélio pigmentar hiperrefletiva, sendo a área macular com maior intensidade. Nesses olhos as camadas da retina não estavam totalmente diferenciadas. A depressão foveal ficou claramente evidente pela tomografia de coerência óptica em 23%. CONCLUSÃO: Nos pacientes prematuros com retinopatia da prematuridade, a tomografia de coerência óptica mostrou as camadas da retina pouco diferenciadas com aumento da refletividade na área macular do complexo epitélio retiniano pigmentar-coriocapilar.

  7. A tomografia de córnea e segmento anterior na propedêutica do exame complementar na avaliação de ectasia

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    Bruno de Freitas Valbon

    2013-02-01

    Full Text Available Descrevemos a importância da tomografia de córnea e segmento anterior na propedêutica do exame complementar na avaliação de ectasia. Esta descrição da interpretação clínica dos índices da tomografia de córnea e segmento anterior (Pentacam - Oculus, Wetzlar, Germany neste relato de caso, demonstra a relevância de uma nova tecnologia na avaliação da córnea e segmento anterior na suspeita de ceratocone. O diagnóstico de ceratocone foi excluído pela análise dos índices tomográficos de ectasia. Detectou-se assimetria entre os lados nasal e temporal por meio da avaliação do mapa de profundidade de câmara anterior. No exame biomicroscópico sob midríase foi constatado subluxação do cristalino, sendo assim devemos estar atentos não somente aos índices tomográficos corneanos na avaliação do exame complementar e sim analisarmos outros dados importantes oferecidos pela tomografia de córnea e segmento anterior.

  8. Tomografia de coerência óptica na commotio retinae: relato de caso Optical coherence tomography imaging in commotio retinae: case report

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    Celso Morita

    2009-08-01

    Full Text Available O objetivo deste relato é correlacionar achados à tomografia de coerência óptica e prognóstico visual de pacientes com commotio retina e de gravidades diferentes. Dois pacientes do sexo masculino, de 20 e 23 anos com baixa visual unilateral após trauma ocular contuso atribuível a edema de Berlin foram avaliados pela retinografia e tomografia de coerência óptica. A acuidade visual no olho afetado era de 20/25 no primeiro paciente e conta dedos a 2 metros no segundo. O exame oftalmológico revelou uveíte traumática e, na fundoscopia, evidenciaram-se opacificação retiniana moderada no primeiro caso e grave no segundo. A tomografia de coerência óptica confirmou discreta diminuição da depressão foveal no primeiro caso e desorganização das camadas retinianas no segundo. Houve resolução anatômica e funcional completa a tomografia de coerência óptica no primeiro paciente, enquanto o segundo evoluiu com baixa visual permanente e desorganização da arquitetura retiniana. A tomografia de coerência óptica é um exame complementar útil na avaliação do trauma retiniano, ajudando a entender sua fisiopatologia e predizer prognóstico a partir da análise anatômica da região acometida.The purpose of this case report was to correlate optical coherence tomography findings and visual outcomes of patients with different degrees of commotio retinae. A 20-year-old male and a 23-year-old male that presented with decreased vision due to Berlin's edema after blunt ocular trauma were evaluated by optical coherence tomography and retinography. The visual acuity in the affected eye was 20/25 in the first patient and counting fingers in the second one. The ophthalmic examination showed traumatic uveitis and fundoscopy revealed mild retinal opacification in the first case and severe opacification in the latter. The optical coherence tomography confirmed the reduction of foveal depression on the first case and the disarrangement of all retinal

  9. LINFOMAS PULMONARES: CORRELAÇÃO DA TOMOGRAFIA COMPUTADORIZADA DE ALTA RESOLUÇÃO COM A ANATOMOPATOLOGIA

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    Marchiori Edson

    2002-01-01

    Full Text Available Neste trabalho são descritos os aspectos tomográficos de alta resolução dos linfomas pulmonares e feita correlação com os achados anatomopatológicos. Com este objetivo, foram revisados as tomografias computadorizadas de alta resolução do tórax e os dados histopatológicos de dez pacientes com diagnóstico confirmado de linfoma não-Hodgkin ou de doença de Hodgkin. Os resultados obtidos foram confrontados com os descritos na literatura. Os achados radiológicos mais comumente vistos neste estudo foram as consolidações parenquimatosas, localizadas, com broncogramas aéreos de permeio (n = 8. Em menor freqüência, foram encontrados múltiplos nódulos parenquimatosos (n = 4, espessamento peribroncovascular (n = 3 e opacidades em vidro fosco (n = 2. Na correlação com a anatomia patológica, as consolidações corresponderam a preenchimento alveolar por células neoplásicas, o espessamento peribroncovascular se deveu a infiltração das bainhas peribroncovasculares por células linfomatosas e a atenuação em vidro fosco se associou com infiltração dos septos alveolares por tais células.

  10. Computerized tomography findings in Fahr's syndrome Achados da tomografia computadorizada na síndrome de Fahr

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    Andréia V. Faria

    2004-09-01

    Full Text Available We analyzed computerized tomography (CT findings in six patients with Fahr's syndrome. They presented calcifications in basal ganglia, dentate nucleus, subcortical region and semioval center, due to alteration in calcium metabolism or due to senile relative hypoxemic state. The image pattern was not strictly related with etiology, although some differences in dystrophic senile calcifications (the only one present in semioval center and absent in subcortical region. CT is an easy exam, has maximum sensitivity and allows diagnosis, contributing to early treatment of many etiologies of Fahr's syndrome.Analisamos os achados de tomografia computadorizada (TC de seis pacientes com síndrome de Fahr. Eles apresentaram calcificações nos gânglios da base, núcleo denteado, região subcortical e centro semi-oval, devidas a distúrbios no metabolismo do cálcio ou a estado de hipóxia relativa, por senilidade. O padrão de imagem não apresenta relação clara com a etiologia, apesar de algumas diferenças no caso das calcificações distróficas senis (as únicas presentes nos centros semi-ovais e ausentes na região subcortical. TC é um exame de fácil realização, máxima sensibilidade e permite o diagnóstico, contribuindo para o tratamento precoce de muitas das etiologias da síndrome de Fahr.

  11. Tomografia computadorizada e ressonância magnética nos oligodendrogliomas: correlação clínica e patológica

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    Simão Marcelo Novelino

    2001-01-01

    Full Text Available Oligodendrogliomas são neoplasias do tecido neuroepitelial glial originárias de oligodendrócitos. São tumores infreqüentes, responsáveis por cerca de 4% a 7% das neoplasias primárias do cérebro, predominantemente supratentoriais. O presente trabalho consistiu na avaliação dos achados de imagem pré-operatória em tomografia computadorizada e ressonância magnética e correlação clínica e patológica, levando-se em consideração a presença de tumores puros ou mistos, com componente astrocitário e o seu grau de anaplasia. O aspecto mais freqüente foi o de lesão hipodensa na tomografia computadorizada ou com hipossinal em T1 e hipersinal em T2 na ressonância magnética, podendo ter componente cístico, com pouco edema ao redor, apresentando calcificações, quase sempre grosseiras, em dois terços dos casos. Reforço após contraste ocorre em 80% dos casos, na maioria discreto.

  12. Tomografia computadorizada sem contraste intravenoso no abdome agudo: quando e por que usar When and why use unenhanced computed tomography in patients with acute abdomen

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    Edison de Oliveira Freire Filho

    2006-02-01

    Full Text Available A tomografia computadorizada sem contraste intravenoso tem sido freqüentemente proposta na avaliação inicial de pacientes com suspeita de abdome agudo, ocupando o espaço de outros métodos diagnósticos. Os autores apresentam uma revisão bibliográfica dos principais aspectos e eficácia da tomografia computadorizada sem contraste intravenoso no diagnóstico de apendicite aguda, cólica nefrética, diverticulite, pancreatite aguda, apendicite epiplóica, pneumoperitônio e obstrução intestinal. Discutem quais as vantagens e limitações desta técnica de exame, bem como seus aspectos práticos.The use of unenhanced computed tomography has been frequently recommended for the initial assessment of patients with clinical suspicion of acute abdomen instead of other diagnostic methods. The authors present a review of the literature on the main aspects, advantages, limitations and efficacy of unenhanced computed tomography for the diagnosis of acute appendicitis, renal colic, diverticulitis, acute pancreatitis, primary epiploic appendicitis, pneumoperitoneum and small bowel obstruction. The advantages and limitations of this technique are also discussed.

  13. Tomografia computadorizada no diagnóstico da otosclerose retrofenestral Computed tomography in the diagnosis of retrofenestral otosclerosis

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    Andy de Oliveira Vicente

    2004-01-01

    Full Text Available OBJETIVO: Identificar os principais achados tomográficos da otosclerose retrofenestral. MÉTODO: Estudo prospectivo multicêntrico com tomografia computadorizada (TC de ossos temporais em 54 pacientes com diagnóstico clínico e cirúrgico de otosclerose. Foi realizada uma análise tomográfica, em que foi avaliada a utilidade da TC no diagnóstico radiológico da otosclerose retrofenestral, sendo verificados os principais sítios de lesões dessa doença. Foram incluídos neste estudo 22 pacientes submetidos à TC de ossos temporais para investigação de outras afecções otológicas, que constituíram o grupo controle. RESULTADOS: Os achados tomográficos foram bilaterais na maioria dos casos e o foco retrofenestral mais prevalente foi o foco pericoclear. CONCLUSÕES: A TC monstrou-se útil na identificação dos focos retrofenestrais. A evidência tomográfica desses focos juntamente com o envolvimento endosteal da cóclea podem sugerir uma maior atividade da doença.AIM: To identify the main tomographic findings of retrofenestral otosclerosis. METHODS: A prospective and multicentric study using computed tomography (CT of the temporal bone in 54 patients with a clinical and surgical diagnosis of otosclerosis. A tomographic analysis has been performed to evaluate the utility of CT scans in diagnosing retrofenestral otosclerosis, verifying the sites of predilection for otosclerotic lesions. In this study, 22 patients undergone CT scans of temporal bones have been included in order to investigate other otologic diseases and have constituted the control group. RESULTS: The tomographic findings were mostly bilateral and the retrofenestral focus more prevalent was the pericochlear focus. CONCLUSIONS: The CT scan was useful in the identification of the retrofenestral focuses. The evidence of this focuses and the presence of the endosteal involvement of the cochlea can suggest a higher activity of the disease.

  14. CT diagnosis of subphrenic abscess after splenectomy for trauma; Ruolo della tomografia computerizzata nella valutazione degli ascessi subfrenici dopo splenectomia post-traumatica

    Energy Technology Data Exchange (ETDEWEB)

    Salzano, A. [Ospedale Loreto-Mare, Neaples (IT). Serv. di Radiologia] [and others

    1999-09-01

    The paper studies subphrenic inflammatory abscesses and splenic fluid collections after splenectomy for trauma. These complications may appear early or late postoperatively; they are easily demonstrated with computerized tomography, which permits accurate spatial assessment of the lesions and appropriate treatment with percutaneous drainage. It has been also investigates the diagnostic accuracy of the CT in subphrenic inflammatory conditions after emergency splenectomy for traumatic spleen rupture and found that CT is a precious tool for rapid and easy diagnosis and follow-up of subphrenic abscesses treated with percutaneous drainage. [Italian] Scopo del lavoro e' di valutare il ruolo della tomografia computerizzata nelle flogrosi subfreniche secondarie a splenectomia d'urgenza per rottura traumatica della milza, documentando come tale metodica risulti accurata nel diagnosticare e monitorare in modo semplice e rapido l'evoluzione e il controllo degli ascessi subfrenici trattati con drenaggio percutaneo.

  15. CT findings after normal and unsuccessful functional endoscopic sinus surgery; Ruolod della tomografia computerizzata dopo chirurgia funzionale dei seni paranasali: rilievi normali e valutazioni degli insuccessi chirurgici

    Energy Technology Data Exchange (ETDEWEB)

    Scribano, E.; Ascenti, G.; Bellinvia, A.; Mazziotti, S.; Lamberto, S. [Messina Univ., Messina (Italy). Ist. di Scienze Radiologiche; Cascio, F. [Messina Univ., Messina (Italy). Ist. di Otorinolaringoiatria

    1999-09-01

    The paper investigates the functional endoscopic sinus surgery with the Messer-linger's technique which treats benign or inflammatory diseases of paranasal sinuses resistant to medical therapy. The goal of this type of surgery is to open the obstructed sinus ostia and restore normal aeration and mucociliary clearance. The computerized tomography permits an accurate assessment of extension and results of functional endoscopic sinus surgery. [Italian] L'articolo discute l'uso della tecnica di Messerklinger nella chirurgia funzionale endoscopica dei seni paranasali per il trattamento delle malattie benigne e delle infiammazioni croniche. Essa disostruisce gli osti sinusali ripristinando la normale areazione e la pulizia mucociliare. La tomografia computerizzata consente di valutare l'estensione e i risultati del trattamento chirurgico funzionale, soprattutto nel caso di insuccesso terapeutico, rilevando malattia nasosinusale ricorrente e-o recidiva.

  16. Tomografia computadorizada em pacientes portadores de neurocisticercose com hipertensão intracraniana por hidrocefalia obstrutiva: comparação com ventriculografia com Dimer-X

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    Benedicto Oscar Colli

    1984-06-01

    Full Text Available Estudo das alterações observadas nas tomografias computadorizadas (TCs de 16 casos de neurocisticercose, com hipertensão intracraniana por hidrocefalia. Todos os casos foram submetidos a radiografias simples do crânio e 12, à ventriculografia com Dimer-X. Nas radiografias simples foram observados sinais de hipertensão intracraniana em 7, calcificações em um, e d foram normais. A TC mostrou parênquima cerebral normal em 9 casos e nos 7 restantes áreas hipodensas arredondadas de tamanho variado, com ou sem retenção de contraste na periferia, e/ou calcificações esparsas no parenquima. Hidrocefalia foi a única alteração observada no sistema ventricular nos casos em que o exame foi realizado previamente à derivação do LCR. As ventriculografias foram analisadas em trabalho anterior e permitiram localizar e determinar as características da obstrução e a presença de massas ocupando espaço dentro dos ventrículos. A comparação das ventriculografias e TCs realizadas na mesma época evidenciou que a primeira fornece melhores informações sobre o sistema ventricular mas, por outro lado, a tomografia fornece informações adicionais sobre o parênquima cerebral. A TC e a ventriculografia são exames que se completam na avaliação e no diagnóstico destes pacientes.

  17. Paracoccidioidomicose pulmonar: relato de caso clínico com aspetos em tomografia computorizada de alta resolução

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    M. Armas

    2012-07-01

    Full Text Available Resumo: A Paracoccidioidomicose é uma micose sistémica endémica nas áreas rurais da América Latina, uma fonte importante de imigrantes e destino de emigração e turismo europeu, a maioria dos casos ocorrendo no Brasil, Argentina, Venezuela e Colômbia. Os autores descrevem o caso clínico de um paciente com 43 anos, anteriormente emigrado na Venezuela e residente em Portugal há 8 anos, que se apresenta com lesão cutânea isolada. Embora sem queixas relevantes do foro respiratório, apresentava extensas lesões do parênquima pulmonar caracterizadas por tomografia computorizada de alta resolução (TCAR. Foi realizada biópsia da lesão cutânea e exame micológico da expetoração que revelaram infeção por Paracoccidioides brasiliensis (PB. Abstract: Paracoccidioidomycosis is a systemic mycosis which is endemic in rural areas of Latin America, an important European source of immigrants and a growing European touristic destination as well, with most cases occurring in Brazil, Argentina, Venezuela and Colombia. The authors report a case of a 43 year old man who previously worked in Venezuela and is living in Portugal for 8 years, presenting with a single cutaneous lesion. Despite the absence of valuable respiratory complaints, severe lung damage was found with high-resolution computed tomography (HRCT. Biopsy of the cutaneous lesion and mycologic sputum examination were performed revealing Paracoccidioides brasiliensis infection. Palavras-chave: Paracoccidioidomicose, Paracoccidioides brasiliensis, Fibrose pulmonar, Tomografia computorizada de alta resolução, Keywords: Paracoccidioidomycosis, Paracoccidioides brasiliensis, Pulmonary fibrosis, High-resolution computed tomography

  18. Hepatocellular carcinoma: computed tomography assessment after invasive treatment;Hepatocarcinoma: Evaluacion con tomografia computada luego del tratamiento intervencionista

    Energy Technology Data Exchange (ETDEWEB)

    Kozima, Shigeru; Larranaga, Nebil; Wulfson, Gabriela [Servicio de Diagnostico por Imagenes Hospital General de Agudos ' Cosme Argerich' , CABA, Buenos Aires (Argentina); Departamento de Imagenes, CEMIC, Buenos Aires (Argentina); Eisele, Guillermo [Departamento de Imagenes, CEMIC, Buenos Aires (Argentina); Ridruejo, Ezequiel; Mando, Oscar [Seccion de Hepatologia. Departamento de Medicina, CEMIC, Buenos Aires (Argentina); Perazzo, Florencia [Seccion Oncologia. Departamento de Medicina, CEMIC, Buenos Aires (Argentina)

    2008-07-01

    Objective: To show the computed tomography (CT) usefulness after treatment with transcatheter arterial quimioembolization and radiofrequency ablation of hepatocellular carcinoma. Material and methods: In a period between march 2006 to april 2008 a total of 90 patient presenting 148 nodular lesions with diagnosis of hepatocellular carcinoma were controlled with triphasic CT. All the lesions were treated with minimally invasive procedure. For the treatment, the patients were classified in two groups following Milan criteria. The first group, constituted by 75 patients with 109 nodules, was treated with quimioembolization. The second group, of 15 patients with 25 nodules, was treated with radiofrequency ablation. In our population, a subgroup of 10 patients was treated with both methods. Results: Of 90 patients after CT control on a month, 3 months and for each 3 months during 2 years, on 63 cases (70%) was observed homogeneous accumulation of iodized oil, partial defect without enhancement or absence of enhancement on treated lesions. In these patients a new treatment after initial one was not performed. The remaining 27 patients (30%) underwent new treatment because we founded partial defect or absence of iodized oil with enhancement or peripheral enhancement on arterial phase in treated lesions. In this last group, 16 treated patients (17.7%) had new nodular enhancement on the remaining hepatic parenquimal. Conclusion: The CT unenhanced and the arterial phase on a month and for each 3 months, allow monitoring the effectiveness, residual disease and/or relapse of hepatocellular carcinoma after minimally invasive treatment. (authors);Objetivo: Mostrar la utilidad de la tomografia computada trifasica (TCT) luego del tratamiento con quimioembolizacion y ablacion por radiofrecuencia (RF) del hepatocarcinoma (HCC). Material y metodos: En un periodo comprendido entre marzo de 2006 y abril de 2008 se controlaron con TCT 90 pacientes que presentaron 148 lesiones nodulares y

  19. Esclerose sistêmica progressiva: aspectos na tomografia computadorizada de alta resolução Progressive systemic sclerosis: high-resolution computed tomography findings

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    Emerson L. Gasparetto

    2005-09-01

    Full Text Available OBJETIVO: Descrever os achados de tomografia computadorizada de alta resolução de pacientes com esclerose sistêmica pulmonar, independentemente dos sintomas respiratórios. MATERIAIS E MÉTODOS: Foram revisados 73 exames de tomografia computadorizada de alta resolução de 44 pacientes com diagnóstico de esclerodermia estabelecido através de critérios clínicos e laboratoriais. Os exames foram revisados por dois radiologistas, que estabeleceram os achados por consenso. RESULTADOS: Em 91,8% (n = 67 dos exames observaram-se alterações. Os principais achados foram lesões de padrão reticular (90,4%, opacidades em vidro-fosco (63%, bronquiectasias e bronquiolectasias de tração (56,2%, dilatação esofagiana (46,6%, faveolamento (28,8% e sinais de hipertensão pulmonar (15,6%. Na maioria dos casos as lesões eram bilaterais (89% e simétricas (58,5%. Quanto à localização, houve predomínio de lesões basais (91,2% e periféricas (92,2%. CONCLUSÃO: A esclerose sistêmica progressiva acarreta fibrose pulmonar na maioria dos pacientes, caracterizada principalmente por lesão reticular basal e periférica.OBJECTIVE: To describe the high-resolution computed tomography findings in the lung of patients with systemic sclerosis, independently of the respiratory symptoms. MATERIALS AND METHODS: Seventy-three high-resolution computed tomography scans of 44 patients with clinical diagnosis of systemic sclerosis were reviewed and defined by the consensus of two radiologists. RESULTS: Abnormalities were seen in 91.8% (n = 67 of the scans. The most frequent findings were reticular pattern (90.4%, ground-glass opacities (63%, traction bronchiectasis and bronchiolectasis (56.2%, esophageal dilatation (46.6%, honeycombing pattern (28.8% and signs of pulmonary hypertension (15.6%. In most cases the lesions were bilateral (89% and symmetrical (58.5%. The lesions were predominantly located in the basal (91.2% and peripheral (92.2% regions. CONCLUSION: In

  20. Nasoangiofibroma juvenil: concordância interobservadores no estadiamento por tomografia computadorizada Juvenile nasopharyngeal angiofibroma: interobserver agreement in cancer staging using computed tomography

    Directory of Open Access Journals (Sweden)

    Jefferson Luiz Gusso

    2001-08-01

    Full Text Available Com o advento da tomografia computadorizada, a avaliação dos locais de acometimento e extensão do nasoangiofibroma juvenil tornou-se mais precisa, o que facilitou o correto estadiamento pré-operatório. O objetivo deste trabalho é avaliar a concordância interobservadores, por meio da análise por tomografia computadorizada, de 15 casos de nasoangiofibroma juvenil em relação à extensão para locais relacionados com altos índices de recidivas. Todos os pacientes eram do sexo masculino, com idade média de 15,8 anos. A análise da concordância entre os observadores quanto à extensão e envolvimento da fossa infratemporal, seios esfenóide e cavernoso e fossa craniana média foi excelente, em relação à fissura orbitária superior foi boa e em relação à base do processo pterigóide e fossa craniana anterior foi ruim. Concluiu-se que a análise apresenta alta concordância entre os observadores para os locais estabelecidos, com exceção da base do processo pterigóide e da fossa craniana anterior.The advent of computed tomography permitted a much more precise evaluation of tumor localization, thus facilitating presurgical staging. The objective of this study was to evaluate the interobserver agreement on the analysis of computed tomography scans of 15 patients with juvenile nasopharyngeal angiofibroma, regarding assessment of tumor extension to sites of high recurrence rate. All patients were male and had a mean age of 15.8 years. The results of the interobserver agreement analysis regarding tumor invasion and extension to the infratemporal fossa, cavernous sinus, sphenoid sinus and medium cranial fossa were excellent. Identification of involvement of the superior orbital fissure was considered good. Interobserver agreement regarding tumor extension to the base of pterigoid process and anterior cranial fossa was considered poor. We concluded that there is a very good interobserver agreement on the evaluation of the established

  1. Edema pulmonar hidrostático: aspectos na tomografia computadorizada de alta resolução Hydrostatic pulmonary edema: high-resolution computed tomography aspects

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    Cláudia Maria Cunha Ribeiro

    2006-12-01

    Full Text Available OBJETIVO: A proposta deste estudo foi caracterizar por meio de tomografia computadorizada de alta resolução do tórax as principais alterações pulmonares do edema pulmonar hidrostático. MÉTODOS: Foram analisadas, retrospectivamente, as tomografias de quinze pacientes com quadro clínico de edema pulmonar hidrostático, divididos em cinco principais grupos etiológicos: insuficiência cardíaca congestiva, valvulopatia mitral aguda, infarto agudo do miocárdio, miocardite e mediastinite fibrosante, tendo sido sete pacientes classificados no primeiro grupo e dois em cada um dos demais. RESULTADOS: Os principais achados do edema hidrostático foram opacidades em vidro fosco (100%, espessamento dos septos interlobulares (100%, derrame pleural (87% e espessamento do interstício peribroncovascular (80%. Outros achados menos comuns foram aumento do calibre dos vasos, consolidações e nódulos do espaço aéreo. CONCLUSÃO: O padrão predominante encontrado nos pacientes estudados foi o de opacidades em vidro fosco associadas a espessamento dos septos interlobulares (padrão de pavimentação em mosaico, com derrame pleural bilateral, predominante à direita.OBJECTIVE: This study aimed to use high-resolution computed tomography scans of the chest to characterize the principal alterations occurring in cases of hydrostatic pulmonary edema. METHODS: A retrospective analysis was made of the tomography scans of 15 patients presenting clinical profiles of hydrostatic pulmonary edema. The cases were divided into five groups by etiology: congestive heart failure (n = 7; acute mitral valve disease (n = 2; acute myocardial infarction (n = 2; myocarditis (n = 2; and fibrosing mediastinitis (n = 2. RESULTS: The principal findings in the cases of hydrostatic pulmonary edema were ground-glass opacities (in 100%, interlobular septal thickening (in 100%, pleural effusion (in 87% and peribronchovascular interstitial thickening (in 80%. Other, less common

  2. Multiphasic helical CT of hepatocellular carcinoma. Evaluation after chemoembolization; Tomografia Computerizzata spirale multifasica dell'epatocarcinoma. Valutazione dopo chemioembolizzazione

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, O.; Esposito, M.; Sandomenico, F.; Siani, A. [Ospedale S. Maria delle Grazie, Pozzuoli, NA (Italy). Servizio di Radiologia; Nunziata, A. [Ospedale S. Maria delle Grazie, Naples (Italy). Area di Diagnostica per Immagini

    2000-06-01

    technique has several limitations, as also shown in recent literature papers and its clinical applications should be reduced. Multiphase helical studies may provide useful information and should be performed routinely in patients treated with chemo embolization. The present availability of alternative tools such as contrast-enhanced Doppler US and MRI should also be stressed and their potential role investigated. [Italian] Il presente lavoro si propone di illustrare la personale esperienza sull'integrazione della Tomografia Computerizzata (TC) senza mdc ev (Lipiodol-TC) con la TC spirale con mdc ev multifasica nella valutazione dei pazienti con epatocarcinoma trattati con chemioembolizzazione e analizzare il possibile ruolo attuale della TC con mdc oleoso. Si sono valutati retrospettivamente gli esami di 42 pazienti consecutivi sottoposti a chemioembolizzazione globale nell'arco di 2 anni. Lo studio con TC e' stato praticato 1830 giorni dopo il trattamento. La Lipiodol-TC e' stata eseguita con acquisione volumetrica; si sono considerati noduli quelle aree delimitate con ritenzione densa del mdc oleoso e si sono distinti la captazione in: 0=assente, I=inferiore a 10% dell'area del tumore, II=minore di 50%, III=maggiore di 50%, IV=omogenea. Lo studio con TC spirale con mdc ev e' stato praticato con tecnica bifasica in 28 pazienti e trifasica in 14; abbiamo ritenuto come nodulari quelle aree ben delimitate e relativamente omogenee con iperdensita' nella fase arteriosa e ipo-isodensita' in quella portale e/o tardiva oppure con ipo-isodensita' nella fase arteriosa e in quella portale e/o tardiva. Con la Lipiodol-TC sono stati identificati 65 noduli (1-5/paziente, media 1,5), 15 con grado I, 21 con grado II, 20 con grado III e 9 con grado IV. Con la TC multifasica sono stati dimostrati 6 noduli supplementari in 5 pazienti, di cui 5 iper-e uno ipovascolare, ed e' stata documentata meglio la reale morfovolumetria dei noduli con

  3. Studio del danneggiamento mediante tomografia in luce del sincrotrone: impatto di un cono d’ombra sulla qualità finale delle ricostruzioni

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    Andrea Bernasconi

    2010-07-01

    Full Text Available Un’accurata osservazione della geometria tridimensionale di cricche e difetti è necessaria per lo studio dei meccanismi alla base del processo di danneggiamento. I metodi convenzionali utilizzati a questo scopo sono distruttivi o non possiedono una sufficiente risoluzione. Le tecniche di imaging che utilizzano la luce di sincrotrone, ed in particolare la microtomografia (micro-CT a raggi X, invece, uniscono i vantaggi di una tecnica non distruttiva ad un’elevata risoluzione spaziale e risultano quindi particolarmente interessanti. Un limite all’applicazione di questa tecnica è costituito dalla propensione della cricca a richiudersi una volta rimosso il carico che ha provocato il danneggiamento, superabile attraverso l’impiego di un dispositivo in grado di esercitare un carico di trazione durante l’acquisizione dei dati. Facendo riferimento al set-up sperimentale della linea SYRMEP di Elettra, il sincrotrone di Trieste, e tralasciando per il momento i vincoli legati a pesi e ingombri, è possibile pensare di inserire tra camera di ionizzazione e CCD una macchina per prove di trazione mono-colonna commerciale, in grado di mantenere aperto il difetto per tutta la durata della tomografia. In questo lavoro viene valutato l’impatto di questo vincolo sulla qualità finale delle ricostruzioni.

  4. Gunshot wounds to the head. Correlations between CT and clinical findings, neurosurgical treatment and long-term sequels; Traumi cranio-encefalici da proiettile: correlazione tra tomografia computerizzata, clinica, trattamento neurochirurgico e sequele a distanza

    Energy Technology Data Exchange (ETDEWEB)

    Salzano, A.; Nocera, V. [Ospedale S. Giovanni di Dio, Frattamaggiore, NA (Italy). Servizio di Radiologia; De Rosa, A.; Nunziata, A. [Ospedale Loreto Mare, Neaples (Italy). Servizio di Radiologia; Rossi, E.; Brunese, L. [Universita' degli Studi Federico II, Neaples (Italy). Ist. di Scienze Radiologiche; Tuccillo, M. [Azienda Ospedaliera di Rilievo Nazionale A. Cardarelli, Neaples (Italy). Servizio di Radiologia; Grassi, R. [Seconda Universita' degli Studi, Neaples (Italy). Ist. di Radiologia

    2000-03-01

    With the aim of demonstrating the usefulness of computerised tomography (CT) findings in the planning of brain neurosurgery in gunshot victims, for prompt and successful treatment, 30 patients with brain gunshot wounds were examined with CT over 5 years. The mortality rate of firearm wounds of the skull base was 34% higher than that of the hemisphere; this is due to carotid hemorrhage and midbrain damage. Such traumas require emergency radiological diagnosis and neurosurgical treatment because of their severity and early irreversible complications. Complex operations and skilled surgeons may prevent disabling postoperative sequels. CT findings are indispensable and must be correctly interpreted. The radiologist and the neurosurgeon must collaborate closely and both must consider several diagnostic factors affecting surgical planning. [Italian] Scopo dello studio e' stato quello di dimostrare l'utilita' della semeiologia della tomografia computerizzata in relazione con la pianificazione dell'intervento neochirurgico, al fine di attuare con tempestivita' interventi chirurgici soddisfacenti e meno lesivi. Lo studio comprende 30 casi di lesioni cranio-encefaliche da arma da fuoco esaminate con tomografia computerizzata nel periodo di 5 anni. Materiali e metodi utilizzati sono analiticamente descritti. L'esperienza dimostra che nelle lesioni da arma da fuoco del basicranio si nota una mortalita' del 34% superiore rispetto a quelle piu' craniali come quelle emisferiche in relazione a emorragie carotidee e lesioni tronco-mesencefaliche. Tali traumi esigono diagnosi radiologica e terapia neurochirurgica d'urgenza per la gravita' e le precoci complicanze irreversibili. Cio' richiede interventi complessi e manualita' esperte e rapide al fine di evitare sequele postoperatorie invalidanti. La corretta e indispensabile interpretazione dei segni radiologici della tomografia computerizzata deve avvenire in stretta

  5. Detecção de fraturas radiculares em imagens de tomografia computadorizada de feixe cônico utilizando diferentes parâmetros de exposição e materiais intracanais

    OpenAIRE

    Pinto, Martina Gerlane de Oliveira

    2015-01-01

    O objetivo deste estudo foi avaliar a detecção de fraturas radiculares (FRs) em imagens de Tomografia Computadorizada de Feixe Cônico (TCFC) utilizando diferentes parâmetros de exposição e analisar a influência da guta- percha, do núcleo metálico fundido e do pino de fibra de vidro no diagnóstico das FRs, assim como a formação de artefatos em TCFC. Cento e sessenta dentes foram selecionados e divididos em quatro grupos de acordo com o material de preenchimento (sem guta-percha, com guta-perch...

  6. O valor da fase sem contraste na tomografia computadorizada do abdome The role of the unenhanced phase in the routine abdominal computed tomography

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    Ana Paula Klautau Leite

    2008-10-01

    Full Text Available OBJETIVO: Determinar o valor agregado da fase sem meio de contraste da tomografia computadorizada do abdome em pacientes sem diagnóstico determinado ou em estadiamento tumoral. MATERIAIS E MÉTODOS: Estudo prospectivo e transversal em 100 pacientes consecutivos submetidos a tomografia computadorizada abdominal sem e com meio de contraste intravenoso. Dois examinadores avaliaram todos os exames, procurando estabelecer, através da fase com meio de contraste intravenoso (primeira análise e posteriormente através da fase sem contraste (segunda análise, o diagnóstico principal e os secundários em função da indicação clínica do exame. Mediu-se a freqüência de mudança diagnóstica decorrente da análise combinada das fases pré- e pós-contraste intravenoso. Casos que tiveram mudança diagnóstica foram avaliados por especialistas clínicos para determinar se implicaria mudanças de conduta. RESULTADOS: Diagnósticos principal e secundário foram modificados em 1 e 18 casos, respectivamente (p = 1,000; p = 0,143. Os diagnósticos modificados foram: esteatose, definição de nódulo em adrenal, nefrolitíase, classificação de cistos renais e calcificação hepática. Nos casos em que a fase sem contraste modificou o diagnóstico, os especialistas mudaram sua conduta em 14/19 (73% dos pacientes (p = 0,038. CONCLUSÃO: A fase sem contraste não modificou significativamente o diagnóstico principal ou secundário. Porém, as mudanças nos diagnósticos secundários influenciaram na conduta adotada pelos especialistas.OBJECTIVE: To determine the role of the unenhanced phase of abdominal computed tomography in patients without a definite diagnosis or undergoing tumor staging. MATERIALS AND METHODS: A prospective and transversal study was developed with 100 consecutive patients submitted to unenhanced and contrast-enhanced abdominal computed tomography. Two observers evaluated all the computed tomography images in the contrast-enhanced phase

  7. Aspectos da tomografia computadorizada no linfoma em pacientes abaixo de 20 anos de idade Computed tomography findings in patients less than 20 years old with lymphoma

    Directory of Open Access Journals (Sweden)

    Adriana Moreira Viana Borba

    2007-04-01

    Full Text Available OBJETIVO: Descrever os achados gerais do linfoma em pacientes abaixo de 20 anos de idade e por subtipo histológico. MATERIAIS E MÉTODOS: Estudo retrospectivo do arquivo digital de tomografia computadorizada do Centro de Controle do Câncer do Hospital Universitário Pedro Ernesto da Universidade do Estado do Rio de Janeiro, no período de março de 2003 a julho de 2005. Dos 22 casos - 16 do sexo masculino e 6 do sexo feminino, com média de idade de 11,5 anos -, 12 eram do subtipo Hodgkin e 10 eram não-Hodgkin. RESULTADOS: Dos achados gerais, verificamos as linfonodomegalias mediastinais como o mais freqüente (59%, com predomínio no grupo Hodgkin (75%, seguido por hepatoesplenomegalia (50% e linfonodomegalias cervicais e retroperitoneais (27,3%. No subtipo Hodgkin houve predomínio do acometimento linfonodal, em sucessivas cadeias, seguido pela hepatoesplenomegalia (50%. Verificamos um caso de massa tonsilar unilateral, opacidade pulmonar em "vidro-fosco" e nódulos renais. No subtipo não-Hodgkin houve predomínio extranodal caracterizado por hepatoesplenomegalia (50%, espessamento de alça intestinal (40%, derrame pleural (30%, nódulo pulmonar (20%, ascite (10%, derrame pericárdico (10% e lesões ósseas mistas (10%. CONCLUSÃO: A tomografia computadorizada é de grande valia no diagnóstico, estadiamento e seguimento do linfoma, com achados de alerta como massa linfonodal, notadamente mediastinal, hepatoesplenomegalia, massa unilateral na tonsila e espessamento parietal de alça intestinal.OBJECTIVE: To describe the general findings of lymphoma and their histological patterns in patients less than 20 years old. MATERIALS AND METHODS: Twenty-two cases (16 male and 6 female, mean age 11.5 years from the digital archive of computed tomography at the Cancer Control Center of "Hospital Universitário Pedro Ernesto - Universidade do Estado do Rio de Janeiro", Rio de Janeiro, RJ, Brazil, were retrospectively analyzed in the period between

  8. Trauma dos ossos temporais e suas complicações: aspectos na tomografia computadorizada Temporal bone trauma and complications: computed tomography findings

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    Ana Maria Doffémond Costa

    2013-04-01

    Full Text Available A maioria das fraturas dos ossos temporais resulta de traumas cranianos bruscos, de alta energia, estando muitas vezes relacionadas a outras fraturas cranianas ou a politraumatismo. As fraturas e os deslocamentos da cadeia ossicular, na orelha média, representam umas das principais complicações das injúrias nos ossos temporais e, por isso, serão abordadas de maneira mais profunda neste artigo. Os outros tipos de injúrias englobam as fraturas labirínticas, fístula dural, paralisia facial e extensão da linha de fratura ao canal carotídeo. A tomografia computadorizada tem papel fundamental na avaliação inicial dos pacientes politraumatizados, pois é capaz de identificar injúrias em importantes estruturas que podem causar graves complicações, como perda auditiva de condução ou neurossensorial, tonturas e disfunções do equilíbrio, fístulas perilinfáticas, paralisia do nervo facial, lesões vasculares, entre outras.Most temporal bone fractures result from high-energy blunt head trauma, and are frequently related to other skull fractures or to polytrauma. Fractures and displacements of ossicular chain in the middle ear represent some of the main complications of temporal bone injury, and hence they will be more deeply approached in the present article. Other types of injuries include labyrinthine fractures, dural fistula, facial nerve paralysis and extension into the carotid canal. Computed tomography plays a fundamental role in the initial evaluation of polytrauma patients, as it can help to identify important structural injuries that may lead to severe complications such as sensorineural hearing loss, conductive hearing loss, dizziness and balance dysfunction, perilymphatic fistulas, facial nerve paralysis, vascular injury and others.

  9. Características da demanda por tomografia computadorizada crânio-encefálica motivos e custos dos exames

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    Ana Tereza Ramos de Oliveira

    1992-03-01

    Full Text Available Foram levantadas as 2860 tomografias computadorizadas crânio-encefálicas (TCCE feitas em um dos três serviços da cidade do Salvador, Brasil, sendo: caracterizados o perfil do usuário e a procedência da demanda; analisados os motivos dos exames e os custos com TCCE normais e anormais. Foram constatadas frequências altas de exames normais: (a para o sexo feminino (66,0% e até os 54 anos (73,0%, neste sexo (variação de exames normais entre 65 e 80%; (b para o sexo masculino nos grupos <15, 25-34 e 35-44 anos (64,7%; (c para solicitações efetuadas pelos convênios (65,3%; (d pelos seguintes motivos, para homens e mulheres respectivamente: cefaléias (81,3 e 87,5%; desmaios/tonturas (79,3 e 78,6%; convulsões (67,3 e 70%; retardo do desenvolvimento psicomotor (72,0 e 67,7%; «distúrbios endócrinos» (75,0% em cada sexo. Proporções altas de exames anormais foram observadas pelos seguintes motivos e para homens e mulheres, respectivamente: síndrome demencial (91,7 e 83,3%; acidentes vasculares encefálicos (85,1 e 73,7%; doenças infecciosas (76,5 e 78,6%; suspeitas de tumor (65,8 e 55,4%; e traumatismo crâ-nioencefálico, 63,6% no sexo masculino. No total, os custos com as TCC normais corresponderam a US$ 565,255 e com as anormais, US$ 381,247; para os convênios, os custos com TCC normais foram 2,2 vezes superiores ao INAMPS e 2,8 vezes superiores àqueles da medicina privada.

  10. Hemorragia subaracnoídea com tomografia de crânio sem sinais de sangramento Subarachnoidal hemorrhage with cranial tomography without bleeding signals

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    Silvio Francisco

    1997-09-01

    Full Text Available Foram observados 23 casos de pacientes com suspeita clínica de hemorragia subaracnoídea (HSA, com tomografia de crânio (CT sem sinais de sangramento, com diagnóstico definitivo realizado por exame de líquido cefalorraquiano(LCR. Desses, 20 casos foram submetidos a angiografia cerebral. Estabeleceu-se a classificação clínica de Hunt & Hess. Os principais achados neste estudo foram:1 um terço dos pacientes apresentou intervalo de tempo entre o ictus e a realização da CT e do LCR entre 24 e 48 horas, período de maior sensiblidade da CT; 2 dos pacientes estudados com angiografia cerebral, 55% tiveram o diagnóstico de aneurisma com predomínio no território de carótida e cerebral anterior; 3 o grau clínico dominante foi Hunt & Hess I e II. Todos os achados encontrados demonstraram a necessidade da realização de LCR em suspeita de HSA sem sinais de sangramento na CT.We observed 23 pacients with clinical hypothesis of subarachnoidal hemorrhage (SAH having cranial tomography (CT without bleeding signals. The final diagnosis of SAH was made upon the cerebrospinal fluid (CSF results. Twenty cases were submitted to brain angiography. They were focused under the clinical classification of Hunt & Hess. The main results were: 1 1/3 of patients had interval time between 24 and 48 hours after ictus and before CT and CSF making; this was the most sensitive CT time; 2 55% of patients with brain angiography had aneurysm predominantly in the carotid and anterior cerebral artery territory; 3 the dominant clinical degree was Hunt & Hess I e II. Conclusion: the results demonstrate the need of CSF test in case of SAH clinical diagnosis with CT showing no bleeding signals.

  11. Colonografia por tomografia computadorizada na visão do médico encaminhador: qual o seu valor segundo a visão de especialistas?

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    Marcelo Longo Kierszenbaum

    2014-06-01

    Full Text Available Objetivo: Mapear a visão dos cirurgiões sobre o papel da colonografia por tomografia computadorizada (CTC. Materiais e Métodos: Envio de questionário eletrônico aos membros do Colégio Brasileiro de Cirurgiões. O questionário constou de 16 questões de múltipla escolha que abordaram dados demográficos e conhecimentos gerais sobre a CTC. Resultados: Foram obtidas 144 respostas; 90,3% dos especialistas eram homens, 60% com menos de 30 anos de formado, 77,1% eram gastrocirurgiões, 22,9% eram cirurgiões gerais, 53,5% encontravam-se na vida acadêmica e 59,7% exerciam sua atividade profissional em cidades com mais de 500.000 habitantes. Em relação ao conhecimento da CTC, 84,7% conheciam o método, 70,8% sabiam como é realizado, 56,9% relataram conhecer o preparo intestinal utilizado, 31,3% utilizavam o método e 53,5% conheciam algum serviço de CTC na cidade em que atuam. Cerca de metade dos profissionais não conhecia a precisa indicação do método. Profissionais que atuam em cidades com mais de 500.000 habitantes conhecem e utilizam mais o método (p < 0,005. Houve uma tendência de os profissionais com carreira acadêmica utilizarem mais o método. Conclusão: A CTC, embora ainda pouco utilizada em nosso meio, é bastante conhecida, principalmente em grandes centros urbanos e no ambiente acadêmico.

  12. New molecular targets for PET and SPECT imaging in neurodegenerative diseases Novos alvos moleculares para tomografia por emissão de pósitrons (PET e tomografia computadorizada por emissão de fóton único (SPECT em doenças neurodegenerativas

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    Marcel Benadiba

    2012-10-01

    Full Text Available The pathophysiology of neurodegenerative diseases (ND such as Alzheimer's disease (AD and Parkinson's disease (PD has not yet been completely elucidated. However, in the past few years, there have been great knowledge advances about intra-and extracellular proteins that may display impaired function or expression in AD, PD and other ND, such as amyloid beta (Aβ, α-synuclein, tau protein and neuroinflammatory markers. Recent developments in the imaging techniques of positron emission tomography (PET and single photon emission computed tomography (SPECT now allow the non-invasive tracking of such molecular targets of known relevance to ND in vivo. This article summarizes recent findings of PET and SPECT studies using these novel methods, and discusses their potential role in the field of drug development for ND as well as future clinical applications in regard to differential diagnosis of ND and monitoring of disease progression.A fisiopatologia das doenças neurodegenerativas (DN, tais como a doença de Alzheimer (DA e a doença de Parkinson (DP, ainda não é completamente compreendida. No entanto, nos últimos anos, houve grandes avanços em termos do conhecimento sobre proteínas intra e extracelulares, tais como beta-amiloide (Aβ, α-sinucleína, proteína tau e marcadores neuroinflamatórios, que podem ter sua função ou expressão prejudicada na DA, DP ou em outras DN. Progressos recentes nas técnicas de tomografia por emissão de pósitrons (PET e tomografia computadorizada por emissão de fóton único (SPECT permitem hoje em dia a identificação não invasiva de tais alvos moleculares in vivo. Este artigo resume descobertas recentes de estudos de PET e SPECT cerebral usando esses alvos moleculares inovadores e discute o papel potencial dessas técnicas no campo do desenvolvimento de novos medicamentos para as DN, bem como futuras aplicações clínicas em relação ao diagnóstico diferencial e monitoramento da progressão dessas

  13. Carcinoma espinocelular do conduto auditivo externo: estudo por tomografia computadorizada de seis casos Squamous cell carcinoma of the external auditory canal: computed tomography findings in six cases

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    Fábio Mota Gonzalez

    2005-06-01

    Full Text Available OBJETIVO: Analisar a importância da avaliação tomográfica da extensão profunda dos carcinomas espinocelulares do conduto auditivo externo. MATERIAIS E MÉTODOS: Foram realizados exames tomográficos com cortes axiais e coronais com janelas para partes moles e óssea em seis pacientes com carcinoma espinocelular do conduto auditivo externo, com idade variando entre 55 e 71 anos, internados no Hospital Heliópolis, no período entre maio de 1995 e dezembro de 2003. RESULTADOS: Dos seis pacientes, todos apresentavam aumento de partes moles no conduto auditivo externo, cinco (83,3% tinham erosão óssea e invasão da orelha média, quatro (66,7% possuíam comprometimento da mastóide e da glândula parótida, três (50% apresentavam invasão da articulação temporomandibular, dois (33,3% tinham invasão da fossa média, do canal carotídeo e linfonodomegalia júgulo-carotídea alta ipisilateral. CONCLUSÃO: A avaliação da extensão tumoral profunda fornecida pela tomografia computadorizada é importante no estadiamento clínico, possibilitando um planejamento terapêutico mais eficaz.OBJECTIVE: To evaluate the role of computed tomography in the assessment of deep extension of squamous cell carcinoma of the external auditory canal. MATERIALS AND METHODS: In the period between May 1995 and December 2003 six patients with squamous cell carcinoma of the external auditory canal were submitted to computed tomography scan at "Hospital Heliópolis", São Paulo, SP, Brazil, including axial and coronal slices with soft tissue and bone algorithms. RESULTS: Thickening of the soft tissue of the external auditory canal was seen in all patients, bone erosion and invasion of the middle ear in five (83.3%, invasion of the mastoid and parotid gland in four (66.7%, invasion of the temporomandibular joint in three (50%, and invasion of the middle cranial fossa, carotid canal and cervical lymph node enlargement in two (33.3% patients. CONCLUSION: Assessment of

  14. Prognóstico visual de 'crosslinking' para ceratocone com base em tomografia de córnea pré-operatória

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    Lopes Bernardo

    2014-08-01

    Full Text Available Objetivo: Verificar índices tomográficos do pré-operatório de pacientes com ceratocone submetidos à crosslinking corneano (CXL como fatores preditivos para a melhora na acuidade visual corrigidas (AVc após um ano. Métodos: Estudo retrospectivo que incluiu 63 olhos de 53 pacientes com ceratocone progressivo submetidos à CXL segundo o protocolo de Dresden: deseptelização corneana, riboflavina 0,1% por 30 minutos e luz ultra-violeta A (UVA a uma irradiância de 3mW/cm2 por 30 minutos. Foram avaliados exames de tomografia corneana com sistema de Scheimpflug rotacional (Pentacam, Oculus antes do CXL e a acuidade visual corrigida antes e após a cirurgia. A análise estatística foi feita com o teste de Kolmorov-Smirnov, teste t de student e curvas de característica operador-receptor (ROC. Resultados: Houve diferença estatisticamente significante (p<0,05 entre os pacientes que obtiveram melhora de AVc em um ano e os que não experimentaram melhora na AVc nesse período nos índices tomográficos pré-operatórios relacionados com espessura e volume corneano. Entre os pacientes que obtiveram melhora na AVc todos possuíam volume corneano em 6,0mm maior que 14,55mm3 e 97,2% deles possuíam volume corneano em 6,5mm maior que 17,76mm3. Assim como, 94,29% desses pacientes apresentavam paquimetria média em 4,0mm maior que 487 μm e 82,86% paquimetria no ponto mais fino maior de 421 μm. Conclusão: Pacientes com ceratocone menos avançado (volume e espessura da córnea maiores no período pré-operatório obtiveram mais chances de ter melhora da AVc um ano após CXL. Estudos prospectivos envolvendo outras variáveis relacionadas com a aberrometria total e o estudo biomecânico da córnea são relevantes para se aumentar a capacidade prognóstica do resultado após CXL.

  15. A tomografia computadorizada de alta resolução na avaliação da toxicidade pulmonar por amiodarona High-resolution computed tomography of amiodarone pulmonary toxicity

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    Daniela Peixoto Consídera

    2006-04-01

    Full Text Available OBJETIVO: Avaliar as principais alterações identificadas na tomografia computadorizada de alta resolução do tórax em pacientes com toxicidade pulmonar pela amiodarona. MATERIAIS E MÉTODOS: Foram avaliadas dez tomografias computadorizadas de alta resolução de tórax de pacientes com pneumonite pela amiodarona, seis desses pacientes do sexo masculino e quatro do sexo feminino, com idade média de 73,5 anos. RESULTADOS: Os achados tomográficos mais relevantes foram opacidades lineares ou reticulares em seis casos (60%, pequenos nódulos com densidade elevada em seis casos (60%, consolidações densas em três casos (30% e aumento da densidade do parênquima hepático em cinco de oito casos em que havia estudo tomográfico do abdome superior (62,5%. CONCLUSÃO: A tomografia computadorizada de alta resolução é um exame importante na avaliação de pacientes com toxicidade pulmonar pela amiodarona, devendo ser realizada sempre que houver suspeita deste diagnóstico. O achado de espessamento de septos interlobulares associado a lesões com aumento de densidade é altamente sugestivo deste diagnóstico.OBJECTIVE: To evaluate the main findings of chest high-resolution computed tomography in patients with amiodarone pulmonary toxicity. MATERIALS AND METHODS: Ten patients - six male and four female, average age of 73.5 years - with amiodarone-induced pneumonitis have undergone chest high-resolution computed tomography. RESULTS: The most relevant tomographic findings were linear or reticular opacities in six cases (60%, small high density nodules in six cases (60%, dense consolidations in three cases (30% and increased density in the hepatic parenchyma in five of eight cases in which there was a superior abdomen CT scan (62.5%. CONCLUSION: The high-resolution computed tomography is a valuable non-invasive test for evaluating patients with amiodarone pulmonary toxicity and should always be performed when one suspects of the presence of this

  16. Achados de tomografia computadorizada de alta resolução em pneumonia pelo vírus parainfluenza pós-transplante de medula óssea: relato de caso

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    Emerson L. Gasparetto

    2004-11-01

    Full Text Available RESUMO: Paciente feminina, de 19 anos, transplantada de medula óssea devido a leucemia mielóide crónica, apresentando tosse seca e coriza no 67.º dia após o procedimento. A radiografia de tórax não evidenciou alterações. A tomografia computadorizada de alta resolução do tórax revelou consolidação subsegmentar na periferia do lobo inferior esquerdo e áreas de redução da atenuação nos terços superior e médio dos pulmões. O lavado broncoalveolar demonstrou pesquisa positiva por imunoflorescência direta para anticorpos anti-vírus parainfluenza. Foi instituído tratamento com ribavirina aerolizada durante 10 dias, havendo melhoria clínico-radiológica do quadro infeccioso.REV PORT PNEUMOL 2004; X (6: 485-489 ABSTRACT: Nineteen year-old female patient, who underwent bone marrow transplantation because of chronic myelogenous leukemia, presented with dry cough and coriza sixty-seven days after the procedure. The chest radiograph was normal. The high resolution computed tomography showed a subsegmental air-space consolidation at the periphery of the left inferior lobe and areas of low attenuation at the superior and middle lung zones. The bronchoalveolar lavage demonstrated positive direct fluorescence antibody testing against parainfluenza virus. Treatment with aerolizated ribavirin was instituted during 10 days and the patient showed clinical-radiological improvement.REV PORT PNEUMOL 2004; X (6: 485-489 Palavras-chave: Vírus parainfluenza, tomografia computadorizada de alta resolução, transplante de medula óssea, Key-words: Parainfluenza virus, high resolution computed tomography, bone marrow transplantation

  17. Microlitíase alveolar pulmonar: achados na tomografia computadorizada de alta resolução do tórax em 10 pacientes Pulmonary alveolar microlithiasis: high-resolution computed tomography findings in 10 patients

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    Edson Marchiori

    2007-10-01

    Full Text Available OBJETIVO: Apresentar os achados na tomografia computadorizada de alta resolução (TCAR do tórax da microlitíase alveolar pulmonar. MÉTODOS: Foram estudadas, retrospectivamente, as tomografias de dez pacientes adultos, sete mulheres e três homens, com idade média de 38,7 anos. Os exames foram analisados por dois radiologistas, de forma independente, e as decisões finais foram obtidas por consenso. RESULTADOS: Os achados mais freqüentes foram as opacidades em vidro fosco e as calcificações subpleurais, ambas presentes em 90% dos pacientes estudados. Os outros achados de maior relevância foram pequenos nódulos parenquimatosos, calcificação ao longo dos septos interlobulares, cissuras nodulares, nódulos subpleurais, cistos subpleurais, consolidações densas e padrão de pavimentação em mosaico. CONCLUSÕES: A microlitíase alveolar pulmonar apresenta aspectos na TCAR que são altamente sugestivos da doença, na maior parte dos casos dispensando a realização de biópsias pulmonares.OBJECTIVE: To present the high-resolution computed tomography (HRCT findings of pulmonary alveolar microlithiasis. METHODS: The HRCT scans of 10 adult patients (seven females and three males; mean age, 38.7 years were retrospectively analyzed. The films were studied independently by two radiologists. RESULTS: The most common tomographic findings were ground-glass attenuation and linear subpleural calcifications, which were seen in 90% of the patients. Other relevant findings were small parenchymal nodules, calcification along the interlobular septa, nodular cissures, subpleural nodules, subpleural cysts, dense consolidations, and a mosaic pattern of attenuation. CONCLUSIONS: The HRCT findings presented by individuals with pulmonary alveolar microlithiasis are distinct. In most cases, such findings can form the basis of the diagnosis, eliminating the need to perform a lung biopsy.

  18. Detection of diabetic foveal edema with biomicroscopy, fluorescein angiography and optical coherence tomography Detecção do edema foveal diabético com biomicroscopia, angiografia fluoresceínica e tomografia de coerência óptica

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    Rosana Zacarias Hannouche

    2008-10-01

    Full Text Available To describe different techniques for the detection of diabetic foveal edema. A retrospective review of the detection of diabetic foveal edema. Noncontact lens biomicroscopy is relatively insensitive in mild foveal thickening apparent on optical coherence tomography. Optical coherence tomography measurements can detect early retinal damage in diabetic retinopathy patients.Descrever diferentes técnicas para detecção do edema foveal diabético. Uma revisão da detecção do edema foveal diabético. Biomicroscopia com lente de não contato é relativamente insensível em edema leve aparente na tomografia de coerência óptica. Tomografia de coerência óptica pode detectar precocemente o dano retiniano inicial em pacientes com retinopatia diabética.

  19. Tumores intracranianos em pacientes encaminhados para estudos por tomografia de coerência óptica como portadores de glaucoma sem hipertensão ocular: relato de dois casos Intracranial tumors in patients referred for optical coherence tomography examination as glaucoma suspects: case report

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    Laurentino Biccas Neto

    2009-10-01

    Full Text Available A tomografia de coerência óptica (OCT tem se mostrado muito útil na avaliação de pacientes com glaucoma. São relatadas duas pacientes referidas com a suspeita de glaucoma sem hipertensão para avaliação por tomografia de coerência óptica que, na verdade, eram portadoras de tumores intracranianos - um cordoma de clivo no primeiro caso e um craniofaringeoma no segundo. Os achados à tomografia de coerência óptica - diminuição difusa da espessura da camada de fibras nervosas circumdiscais desproporcionalmente acentuada nos setores nasal e temporal - levantaram a suspeita de acometimento na região do quiasma e permitiram o diagnóstico destes importantes tumores intracranianos.Optical coherence tomography (OCT has proved to be a very valuable tool in the assessment of patients with glaucoma. In this report, intracranial tumors were discovered in two glaucoma suspects referred for diagnostic confirmation by OCT - a clivus chordoma and a craniopharyngeoma. Optical coherence tomography findings - marked asymmetrical diffuse attenuation of the peripapillary nerve fiber layer in nasal and temporal sectors - raised concerns about lesions in chiasmatic region and permitted the timely diagnosis of these intraocular tumors.

  20. Complicações pulmonares após uso de crack: achados na tomografia computadorizada de alta resolução do tórax Pulmonary complications of crack cocaine use: high-resolution computed tomography of the chest

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    Alexandre Mançano

    2008-05-01

    Full Text Available Relatamos os achados na tomografia computadorizada de alta resolução de um paciente que, após uso de cocaína fumada (crack, desenvolveu quadro de hemoptise, dispnéia e dor torácica súbitas. As radiografias de tórax mostravam consolidações predominando em lobos superiores. A tomografia de alta resolução evidenciava opacidades em vidro fosco, consolidações e nódulos do espaço aéreo. Nova tomografia de controle, após suspensão da droga e uso de corticóides, mostrou regressão parcial das lesões e aparecimento de escavações. A correlação entre os achados clínicos, laboratoriais e de imagem permitiu o diagnóstico de "pulmão de crack".Here, we report high-resolution computed tomography (HRCT findings in a patient who developed sudden hemoptysis, dyspnea and chest pain after smoking crack cocaine. Chest X-rays showed consolidations, primarily in the upper lobes, and HRCT scans showed ground glass attenuation opacities, consolidations and air-space nodules. A follow-up CT, after drug use discontinuation and administration of corticosteroids, showed partial resolution of pulmonary lesions and the appearance of cavitations. Clinical, imaging and laboratory findings led to a diagnosis of 'crack lung'.

  1. Análise por tomografia computadorizada do enxerto autógeno na cirurgia de "sinus lift" Computed tomography evaluation of autogenous graft in sinus lift surgery

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    Sérgio Aron Ajzen

    2005-02-01

    Full Text Available OBJETIVO: Quantificar a formação óssea nos enxertos com e sem plasma rico em plaquetas, obtido pelos métodos de centrifugação e aférese, comparando os três tipos de enxertos realizados por meio de análise tomográfica. MATERIAIS E MÉTODOS: Este estudo prospectivo, duplo cego, utilizou uma amostra composta de 34 pacientes adultos, de ambos os sexos, com idade média de 48 anos e 8 meses, portadores de pneumatização unilateral ou bilateral dos seios maxilares, que necessitavam de enxertos ósseos, com a finalidade de melhorar as condições locais para a colocação dos implantes dentários. Todos os pacientes realizaram tomografia computadorizada antes da cirurgia. Foram operados 53 seios maxilares, divididos em três grupos: enxerto de plasma rico em plaquetas obtido pelos métodos de aférese, centrifugação e enxerto apenas de osso autógeno. Após seis meses do procedimento cirúrgico foram realizados novos exames de imagem. RESULTADOS: Pela avaliação tomográfica, houve crescimento em altura e em largura nos três grupos quando foram comparados os momentos inicial e final, entretanto, não houve diferença estatística para a altura e para a largura. CONCLUSÃO: Evidências clínicas demonstram a eficácia dos enxertos autógenos, principalmente os associados a fatores indutores de crescimento ósseo, como o plasma rico em plaquetas, recuperando o arcabouço maxilofacial, necessário para a reconstrução protética e funcional por meio de implantes dentários.OBJECTIVE: To quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from aphaeresis or centrifugation using computed tomography. MATERIALS AND METHODS: This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months, with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental

  2. Retinal thickness assessed by optical coherence tomography (OCT in pseudophakic macular edema Espessura retiniana medida pela tomografia de coerência óptica (OCT no edema macular do pseudofácico

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    Maria Teresa Brizzi Chizzoti Bonanomi

    2006-08-01

    Full Text Available PURPOSE: To evaluate the usefulness of the optical coherence tomography (OCT retinal map in angiographic pseudophakic macular edema (ACME. METHODS: This is a prospective analysis of a group of 36 pseudophakic eyes at the fifth postoperative week, submitted to optical coherence tomography 2 macular map and fluorescein angiography on the same day and, a control group of twenty-two 20/20 vision eyes with a minimum 6-month postoperative period, submitted to optical coherence tomography 2 macular map only. Exclusion criteria were diabetes, any macular pathology and unreadable optical coherence tomography or angiogram. The angiograms were divided into three groups according to the edema intensity: Group I: level 0 (absence of angiographic pseudophakic macular edema; group II: levels 1 and 2 (incomplete and complete perifoveal angiographic pseudophakic macular edema respectively and group III: levels 3 and 4 (up to one disc diameter and greater than one disc diameter angiographic pseudophakic macular edema area respectively. The nine zones of the optical coherence tomography macular map were compared between the control and the three subgroups of the study group and, between group I and groups II and III. RESULTS: Among the 36 eyes, 23 (64% were classified as group I, 10 (28% as group II and three (8% as group III. The mean thickness of the fovea zone was 185±15 µm for the control group, 189±24 µm for group I, 213±33 µm for group II and 455±38 µm for group III. Significant differences: between group III and the control or group I for all zones (pOBJETIVO: Medir a espessura retiniana pela tomografia de coerência óptica (OCT no edema macular angiográfico do pseudofácico (ACME. MÉTODOS: Trabalho prospectivo composto de um grupo de estudo com 36 olhos pseudofácicos, entre a 4ª e a 6ª semana de pós-operatório, submetidos ao mapa macular com a tomografia de coerência óptica 2 e à angiofluoresceinografia no mesmo dia e, um grupo controle

  3. Proposta para padronização do relatório de tomografia computadorizada nos aneurismas da aorta abdominal A proposal for standardizing computed tomography reports on abdominal aortic aneurysms

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    Fabiola Goda Torlai

    2006-08-01

    Full Text Available OBJETIVO: Propor um modelo de padronização de relatório para aneurisma da aorta abdominal na tomografia computadorizada. MATERIAIS E MÉTODOS: Foram realizadas, no período de abril a outubro de 2004, entrevistas com integrantes da Disciplina de Cirurgia Vascular da nossa instituição, para elaboração de um modelo de padronização de relatório de tomografia computadorizada para o estudo do aneurisma da aorta abdominal. A partir deste modelo foi elaborado um questionário, enviado a nove outros cirurgiões, todos com experiência em cirurgia da aorta abdominal. O índice de resposta aos questionários foi de 55,5% (5/9. RESULTADOS: Os parâmetros de interesse citados mais freqüentemente para a avaliação dos aneurismas de aorta abdominal foram: diâmetro máximo do colo proximal, extensão do colo proximal até a artéria renal mais baixa, forma do colo proximal, diâmetro máximo do aneurisma e diâmetro das artérias ilíacas comuns. Estes dados permitiram elaborar uma proposta de modelo para padronização de relatório na tomografia computadorizada. CONCLUSÃO: Um modelo para a análise tomográfica padronizada do aneurisma de aorta abdominal permite atender às necessidades dos cirurgiões vasculares para acompanhar a evolução e planejar o tratamento destes pacientes.OBJECTIVE: To propose a model to standardize computed tomography reports on abdominal aortic aneurysms. MATERIALS AND METHODS: Interviews were carried out with members of Vascular Surgery Division of our institution, in the period between April and October 2004, aiming at developing a standardized model of computed tomography reports on abdominal aortic aneurysms. Based on this model, a questionnaire was elaborated and sent to other nine surgeons, all of them experienced in the field of abdominal aortic surgery. The questionnaires response rate was 55.5% (5/9. RESULTS: The most frequently mentioned parameters of interest for evaluation of abdominal aortic aneurysms

  4. Análise de dentição mista: tomografia versus predição e medida radiográfica Mixed-dentition analysis: tomography versus radiographic prediction and measurement

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    Letícia Guilherme Felício

    2010-10-01

    Full Text Available OBJETIVO: o objetivo dos autores desse estudo foi comparar o método de análise de dentição mista que utiliza tomografia computadorizada de feixe cônico para avaliar os diâmetros dos dentes intraósseos com os métodos de Moyers, Tanaka-Johnston e radiografias oblíquas em 45º. MÉTODOS: foram realizadas medidas, na arcada inferior, dos diâmetros mesiodistais dos incisivos permanentes irrompidos, nos modelos de gesso com auxílio de paquímetro digital e estimativa do tamanho de pré-molares e caninos permanentes ainda não irrompidos utilizando-se a tabela de Moyers e a fórmula de predição de Tanaka-Johnston. Nas radiografias oblíquas em 45º, caninos e pré-molares foram medidos utilizando-se o mesmo instrumento. Nas tomografias, as mesmas unidades dentárias foram aferidas por meio de ferramentas do programa Dolphin. RESULTADOS: a análise estatística revelou elevada concordância entre o método tomográfico e o radiográfico, e baixa concordância entre o tomográfico e os demais avaliados. CONCLUSÃO: a tomografia computadorizada de feixe cônico mostrou-se confiável para análise da dentição mista e apresenta algumas vantagens em relação aos métodos comparados: a observação e mensuração dos dentes intraósseos individualmente, com a possibilidade, contudo, de visualizá-los sob diferentes perspectivas e sem superposição de estruturas anatômicas.OBJECTIVE: The aim of this study was to evaluate the method for mixed-dentition analysis using Cone-Beam Computed Tomography for assessing the diameter of intra-osseous teeth and compare the results with those obtained by Moyers, Tanaka-Johnston, and 45-degree oblique radiographs. METHODS: Measurements of mesial-distal diameters of erupted lower permanent incisors were made on plaster cast models by using a digital calliper, whereas assessment of the size of non-erupted permanent pre-molars and canines was performed by using Moyer's table and Tanaka-Johnston's prediction

  5. Fibrose maciça progressiva em trabalhadores expostos à sílica: achados na tomografia computadorizada de alta resolução Progressive massive fibrosis in silica-exposed workers: high-resolution computed tomography findings

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    Ângela Santos Ferreira

    2006-12-01

    Full Text Available OBJETIVO: Avaliar as características radiológicas das massas conglomeradas pela tomografia computadorizada de alta resolução de tórax. MÉTODOS: Foram selecionados 75 pacientes silicóticos, a maioria jateadores de areia, portadores de fibrose maciça progressiva, atendidos no Hospital Universitário Antônio Pedro entre 1986 e 2004. Os pacientes foram submetidos a avaliação clínica, radiografia simples de tórax e tomografia computadorizada de alta resolução. RESULTADOS: Mais da metade dos pacientes com silicose complicada mostrou na radiografia de tórax grandes opacidades dos tipos B e C, denotando a gravidade da doença nesses pacientes. Dos 75 casos, apenas um apresentou massa unilateral simulando câncer de pulmão. Quarenta e quatro pacientes realizaram tomografia computadorizada de alta resolução do tórax. As massas predominaram nos terços superiores e posteriores (88,6%. Broncograma aéreo e calcificações no interior das massas foram observados em 70,4% e 63,8% dos casos, respectivamente. História de tuberculose foi relatada em 52% dos pacientes estudados. CONCLUSÃO: Na grande maioria dos casos as massas eram bilaterais, predominando nas regiões póstero-superiores dos pulmões, com broncogramas aéreos e calcificações de permeio. Associação com calcificações linfonodais foi um achado freqüente. A exposição a elevadas concentrações de poeira e a tuberculose foram consideradas fatores de risco para o desenvolvimento da fibrose maciça progressiva.OBJECTIVE: To evaluate the radiological characteristics of conglomerate masses using high-resolution computed tomography of the chest. METHODS: From among the patients treated between 1986 and 2004 at the Antonio Pedro University Hospital, 75 patients with silicosis and massive fibrosis, most working in the field of sandblasting, were selected for study. These patients were submitted to a clinical evaluation, chest X-ray and high-resolution computed tomography of

  6. Análise de carcinomas epidermóides por meio de radiografia panorâmica e tomografia computadorizada Analysis of squamous cell carcinomas by means of panoramic radiography and computed tomography

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    Amanda Cáceres PEREIRA

    2001-12-01

    Full Text Available Este trabalho teve como objetivo correlacionar aspectos radiográficos como, localização e extensão do tumor, infiltração óssea e de tecidos moles e destruição das corticais, obtidos nas radiografias panorâmicas com os encontrados nas tomografias computadorizadas (TCs. Os aspectos radiográficos de 48 pacientes com diagnóstico histopatológico de carcinomas epidermóides, localizados em várias regiões do complexo buco-maxilo-facial, foram analisados por 4 radiologistas. As radiografias panorâmicas e as tomografias computadorizadas foram realizadas nos hospitais e clínicas da Universidade de Iowa (EUA, FUNDECTO - USP e Hospital Universitário da Universidade de São Paulo (SP, Brasil. Como resultados, obtivemos a grande limitação da radiografia panorâmica em determinar a localização e extensão do tumor, com delimitações bastante imprecisas da lesão. Já as TCs ofereceram resultados mais direcionados como: invasão do tumor em direção a estruturas moles adjacentes, extensão da destruição óssea, bem como a profundidade da lesão, que foram confirmados com os achados cirúrgicos. Concluímos que a tomografia computadorizada demonstrou ser uma técnica bastante sensível na detecção do comprometimento ósseo e do envolvimento de tecidos moles, proporcionando, assim, o auxílio no diagnóstico e no planejamento do tratamento. No entanto, a radiografia panorâmica foi muito pouco sensível e eficaz, por mostrar apenas margens imprecisas e pouco nítidas da lesão, não avaliando o envolvimento de tecidos moles.The purpose of this work was to compare radiographic findings, such as localization and extension of tumors toward the bone and soft tissues, in panoramic radiography and computed tomography (CT. Four radiologists assessed the radiographic findings of 48 patients with the histopathological diagnosis of squamous cell carcinoma in different sites of the maxillofacial region. Panoramic radiographs and computed

  7. Comparação morfométrica da orelha interna entre ovinos e humanos através da tomografia computadorizada CT-Scan sheep and human inner ear morphometric comparison

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    Valter Ayres Seibel

    2006-06-01

    Full Text Available INTRODUÇÃO: trabalhos sobre o uso de ovelhas em cirurgias experimentais e treinamento em cirurgia otológica são raros. Este estudo pretende contribuir para ampliar o conhecimento nessa área. OBJETIVO: Estudar a orelha interna da ovelha por meio de tomografia computadorizada e cortes sucessivos com o intuito de apresentar dados morfométricos mais precisos relacionados à comparação entre a orelha de ovelhas e a de humanos. MATERIAL E MÉTODO: Foi realizado um estudo descritivo sem seguimento no qual foram comparadas as estruturas da orelha interna da ovelha com as dos humanos. As medidas foram obtidas através de tomografias computadorizadas e avaliadas por meio de um programa de análise de imagens médicas (Osíris 4.16. RESULTADOS: O estudo morfológico da orelha da ovelha, em média, e da orelha humana, em média, revelaram grande similaridade de anatomia. A maior parte das estruturas (10 de 15 preservou a relação proposta de 2/3 da dimensão humana em relação à dimensão ovina. CONCLUSÃO: Os achados contribuem para uso da orelha da ovelha como modelo em cirurgia experimental e treinamento em cirurgia otológica.INTRODUCTION: Studies about the use of sheep in surgical training and experimental otologic surgery are rare. This study intends to contribute to the knowledge on this field. AIM: To study sheep inner ear structures using computerized tomography and serial cross-sections to collect more accurate morphometric data to compare sheep and human ears. MATERIAL AND METHODS: This descriptive study compared the inner structures of sheep and human ears. Measurements were made using computerized tomography, and they were stored in a DICOM compact disc for later analysis and manipulation, with a program used for medical image analysis (Osíris 4.16. RESULTS: Mean measures for sheep and human ears were found to be similar in this morphological study. Most structures (10 out of 15 maintained the 2/3 ratio of sheep to human ear

  8. Quando a fase de equilíbrio pode ser suprimida nos exames de tomografia computadorizada de abdome? What is the real role of the equilibrium phase in abdominal computed tomography?

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    Priscila Silveira Salvadori

    2013-04-01

    Full Text Available OBJETIVO: Avaliar a necessidade de realização da fase de equilíbrio nos exames de tomografia computadorizada de abdome. MATERIAIS E MÉTODOS: Realizou-se estudo retrospectivo, transversal e observacional, avaliando 219 exames consecutivos de tomografia computadorizada de abdome com contraste intravenoso, realizados num período de três meses, com diversas indicações clínicas. Para cada exame foram emitidos dois pareceres, um avaliando o exame sem a fase de equilíbrio (primeira análise e o outro avaliando todas as fases em conjunto (segunda análise. Ao final de cada avaliação, foi estabelecido se houve mudança nos diagnósticos principais e secundários, entre a primeira e a segunda análise. Foi utilizada a extensão do teste exato de Fisher para avaliar a modificação dos diagnósticos principais (p 0,999. Com relação aos diagnósticos secundários, cinco exames (2,3% foram modificados. CONCLUSÃO: Para indicações clínicas como estadiamento tumoral, abdome agudo e pesquisa de coleção abdominal, a fase de equilíbrio não acrescenta contribuição diagnóstica expressiva, podendo ser suprimida dos protocolos de exame.OBJECTIVE: To evaluate the role of the equilibrium phase in abdominal computed tomography. MATERIALS AND METHODS: A retrospective, cross-sectional, observational study reviewed 219 consecutive contrast-enhanced abdominal computed tomography images acquired in a three-month period, for different clinical indications. For each study, two reports were issued - one based on the initial analysis of non-contrast-enhanced, arterial and portal phases only (first analysis, and a second reading of these phases added to the equilibrium phase (second analysis. At the end of both readings, differences between primary and secondary diagnoses were pointed out and recorded, in order to measure the impact of suppressing the equilibrium phase on the clinical outcome for each of the patients. The extension of the exact Fisher

  9. Optical coherence tomography image in gelatinous drop-like corneal dystrophy: case report Tomografia de coerência óptica na distrofia corneana gelatinosa em gotas: relato de caso

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    Otávio de Azevedo Magalhães

    2012-10-01

    Full Text Available Gelatinous drop-like corneal dystrophy is a rare disorder with few cases described in the present literature. The following report will show how difficult it is to diagnose this disease in early stages. Modern image exams, such as optical coherence tomography helps to diagnose and can be crucial to establish the best treatment. We will present the histopathological changes and clinical features in this unusual dystrophy.A distrofia corneana gelatinosa em gotas é uma desordem rara e pouco descrita em nossa literatura. O caso apresentado demonstra a dificuldade de realizar o diagnóstico nas fases mais iniciais da doença. O uso de modernos exames de imagem, como a tomografia de coerência óptica de segmento anterior, auxilia no diagnóstico e pode ser crucial para definir a melhor conduta terapêutica. Apresentaremos as alterações histopatológicas e as características clínicas desta incomum distrofia.

  10. Radiograma de tórax e tomografia computadorizada na avaliação do enfisema pulmonar Chest X-ray and computed tomography in the evaluation of pulmonary emphysema

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    Klaus Loureiro Irion

    2007-12-01

    Full Text Available O enfisema é uma condição do pulmão, caracterizada pelo aumento acima do normal no tamanho dos espaços aéreos distais ao bronquíolo terminal. Atualmente, o enfisema é a quarta causa de morte nos EUA, afetando 14 milhões de pessoas. O presente artigo descreve as principais ferramentas no diagnóstico por imagem do enfisema, desde o início até os dias de hoje. Relata as técnicas tradicionais, como radiograma de tórax, e as evoluções no campo da tomografia computadorizada (TC, como a TC de alta resolução e a densitovolumetria pulmonar por TC tridimensional.Emphysema is a condition of the lung, characterized by the abnormal increase in the size of the airspace distal to the terminal bronchioles. Currently, emphysema is the fourth leading cause of death in the USA, affecting 14 million people. The present article describes the principal tools in the imaging diagnosis of emphysema, from the early days until the present. We describe traditional techniques, such as chest X-ray, together with the evolution of computed tomography (CT to more advanced forms, such as high resolution CT, as well as three-dimensional CT densitometry and volumetric assessment.

  11. Aspectos da tomografia de coerência óptica na doença de Stargardt: relato de caso Optical coherence tomography aspects of Stargardt's disease: case report

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    Enéias Bezerra Gouveia

    2006-08-01

    Full Text Available O termo fundus flavimaculatus (doença de Stargardt descreve um grupo de distrofias maculares hereditárias caracterizadas por múltiplos "flecks" amarelados em nível do epitélio pigmentar da retina. Os autores descrevem os achados de tomografia de coerência óptica (OCT em paciente portador de doença de Stargardt e sugerem que a OCT tem validade como exame subsidiário no estudo das características da retina de pacientes portadores da doença de Stargardt, embora estudos envolvendo maior número de pacientes sejam indicados para permitir traçar-se o perfil das alterações mais comuns nestes casos.The term fundus flavimaculatus (Stargardt disease describes a group of inherited macular dystrophies characterized by multiple yellow to yellow-white flecks at the level of the retinal pigment epithelium. The authors describe findings in the patient with Stargardt's disease using optical coherence tomography (OCT, and suggest the examination to be valid as subsidiary method in the study of the characteristics of the retina in Stargardt's disease patients, but studies involving a series of patients should be able to show the most frequent findings in these cases.

  12. Estudo do metabolismo da glicose na tuberculose pulmonar ativa utilizando a tomografia por emissão de pósitrons (18F-FDG PET Evaluation of glucose metabolism in active lung tuberculosis by positron-emission tomography (18F-FDG PET

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    SIDNEY BOMBARDA

    2002-09-01

    Full Text Available Os métodos de imagem utilizados na avaliação da tuberculose pulmonar incluem a radiografia e a tomografia computadorizada do tórax. As imagens obtidas pelos métodos de medicina nuclear permitem estudos funcionais e metabólicos dos órgãos de interesse, através do uso de radiofármacos específicos. Alterações do metabolismo da glicose podem ser detectadas pela tomografia por emissão de pósitrons (PET utilizando-se o 18F-fluorodesoxiglicose (18F-FDG. Essas alterações estão presentes nas doenças neoplásicas, inflamatórias e infecciosas. A tuberculose é uma doença granulomatosa causada pelo Mycobacterium tuberculosis, que se utiliza de glicose como fonte de energia. Objetivo: O estudo do metabolismo da glicose na tuberculose pulmonar através da PET e sua comparação com a tomografia computadorizada de tórax. Material e métodos: Foram avaliados 20 pacientes portadores de tuberculose pulmonar. Todos foram submetidos à PET e à tomografia computadorizada de tórax, em até 30 dias após o início do tratamento. Resultados: Todos os pacientes apresentaram captação positiva do 18F-FDG na PET. Na tomografia computadorizada do tórax, todos os pacientes apresentaram sinais compatíveis com atividade de tuberculose. A sensibilidade dos dois métodos foi de 100%. Houve concordância entre os achados do 18F-FDG PET e da tomografia computadorizada (K = 0,27 e p Current methods to evaluate lung tuberculosis include chest radiography and computed tomography. Nuclear medicine imaging techniques are performed after administration of specific radiopharmaceuticals that accumulate in the organs of interest. Alterations of glucose metabolism can be observed by positron-emission tomography, using 18F-fluorodeoxyglucose (18F-FDG PET. These findings are present in the neoplasms, but also in inflammatory and infectious diseases. Tuberculosis is a granulomatous disease caused by Mycobacterium tuberculosis , that uses glucose as an energy source

  13. Avaliação do edema macular após cirurgia não complicada de facoemulsificação com implante de lente intraocular por meio da tomografia de coerência óptica spectral domain

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    Everton Paroschi Corrêa

    2013-12-01

    Full Text Available OBJETIVO: Avaliar o edema macular após cirurgia não complicada de facoemulsificação com implante de lente intraocular por meio da tomografia de coerência óptica spectral domain (OCT-SD. MÉTODOS: Foi realizado estudo prospectivo em 62 olhos de pacientes submetidos à facoemulsificação com implante de lente intraocular. Os pacientes foram avaliados antes e após a cirurgia, no primeiro dia, e na primeira, segunda e quarta semanas. Acuidade visual (AV, células na câmara anterior e tomografia de coerência óptica macular cubo 200x200 foram medidos. RESULTADOS: Após a cirurgia de facoemulsificação houve melhora da acuidade visual, inflamação decrescente, e a espessura e o volume macular aumentaram. Ocorreu um caso de edema macular cistoide. Houve correlação inversa fraca entre a acuidade visual e a espessura macular central, e entre a acuidade visual e o volume macular. Foi observada correlação direta fraca entre a inflamação e o volume macular. CONCLUSÃO: Edema macular subclínico desenvolve-se mesmo após cirurgia de catarata não complicada em pacientes não predispostos. A tomografia de coerência óptica spectral domain foi capaz de detectar pequenos aumentos na espessura macular no período avaliado.

  14. Estudo da síndrome de tração macular vítreo-retiniana idiopática por meio da tomografia de coerência óptica: relato de casos A study of idiophatic vitreomacular traction syndrome with optical coherence tomography images: cases report

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    Hélio Paulo Primiano Júnior

    2007-02-01

    Full Text Available OBJETIVOS: Avaliar alterações estruturais observadas na síndrome de tração macular vítreo-retiniana idiopática (STMI pela tomografia de coerência óptica (OCT, antes e depois da vitrectomia; identificar situações em que a tomografia de coerência óptica fornece informações adicionais da morfologia e patogênese desta doença. MÉTODOS: Imagens tomográficas (OCT Stratus comparativas da estrutura vítreo-retiniana foram realizadas em quatro pacientes, em estágios variados da síndrome de tração macular vítreo-retiniana idiopática. RESULTADOS: A tomografia de coerência óptica Stratus apresenta imagens vítreo-retinianas que auxiliam na conduta e tratamento da síndrome de tração macular vítreo-retiniana idiopatica. CONCLUSÃO: O exame da tomografia de coerência óptica permite boa visualização da arquitetura morfológica do vítreo e da retina na síndrome de tração macular vítreo-retiniana idiopática. Este exame nos auxilia na compreensão da patogênese, no planejamento do tratamento, clínico ou cirúrgico, e na avaliação pós-operatória das alterações estruturais retinianas.PURPOSE: To evaluate the features of idiophatic vitreomacular traction syndrome (VMT with ocular coherence tomography (OCT - Stratus, before and after vitrectomy; to identify situations where ocular coherence tomography provides additional information on disease morphology and pathogenesis. METHODS: Comparative retinal ocular coherence tomography imaging was performed in four patients with different stages of vitreomacular traction syndrome. RESULTS: Standard-resolution ocular coherence tomography Stratus provides vitreous-retinal images that help the management and treatment of vitreomacular traction syndrome. CONCLUSIONS: Standard-resolution ocular coherence tomography allows good visualization of the architectural morphology of the vitreous and retina in vitreomacular traction syndrome. It helps understanding its pathogenesis, planning

  15. Esvaziamento gástrico após administração oral de contraste em tomografia computadorizada do abdômen: descrição de seis casos

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    Martins Fernando Antonio Nogueira da Cruz

    2004-01-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A lesão pulmonar secundária à aspiração do conteúdo gástrico é complicação associada à perda dos reflexos protetores das vias aéreas. Neste contexto, a realização de exames tomográficos que incluem a contrastação do trato digestivo exige particular atenção em crianças abaixo de cinco anos, que necessitam anestesia geral ou sedação para assegurar imobilidade durante o procedimento. A indução da anestesia ou sedação, após ingestão da solução de contraste pode trazer risco substancial para a broncoaspiração do conteúdo gástrico. Isto faz com que se opte por administrar o contraste por sonda gástrica após a intubação traqueal, uma vez que não se conhece o tempo de esvaziamento gástrico após utilização de solução contrastante. Esta conduta representa aumento do tempo de anestesia, o que resulta em constante questionamento sobre a possibilidade de esvaziamento do conteúdo gástrico em tempo inferior a uma hora. Seis casos de pacientes submetidos à tomografia de abdômen foram avaliados quanto ao esvaziamento gástrico por meio da realização de cortes tomográficos na topografia do estômago, com o objetivo de determinar a presença ou ausência de conteúdo residual líquido nesse órgão, após a administração da solução de contraste. RELATO DOS CASOS: Foram avaliadas seis crianças submetidas à tomografia contrastada do abdômen. Duas, não anestesiadas, apresentaram expressivo resíduo líquido gástrico decorridos 50 e 45 minutos, respectivamente, da ingestão de contraste. Quatro, submetidas à anestesia geral, também apresentaram resíduo líquido gástrico decorridos 40 a 50 minutos da administração de contraste via sonda oro/nasogástrica. Em duas destas persistiu apreciável resíduo líquido no estômago, mesmo após a aspiração do conteúdo pela sonda. CONCLUSÕES: Nos casos observados, o período de 40 a 50 minutos foi insuficiente para o esvaziamento do

  16. Immediate adverse reactions to intravenous iodinated contrast media in computed tomography Reacciones adversas inmediatas al contraste yodado intravenoso en tomografía computarizada Reações adversas imediatas ao contraste iodado intravenoso em tomografia computadorizada

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    Beatriz Cavalcanti Juchem

    2007-02-01

    ório-descritiva, de caráter não experimental, com o objetivo de conhecer as reações adversas imediatas ao contraste iodado intravenoso em pacientes hospitalizados, submetidos a tomografia computadorizada num hospital-escola no Sul do Brasil. Durante o período de estudo, todas as reações adversas manifestaram-se na intensidade leve, com freqüência de 12,5% com o uso de contraste iodado iônico e 1% com contraste não iônico. Extravasamento do meio radiopaco ocorreu em 2,2% das injeções em veia periférica, não havendo complicações em nenhum dos casos. Os resultados encontram-se dentro dos limites citados na literatura internacional e sugere-se que os serviços de tomografia conheçam as próprias taxas de reações adversas ao contraste iodado e as condições em que elas ocorrem, a fim de obter evidências para a avaliação dos respectivos processos assistenciais.

  17. Avaliação da concordância interobservadores na análise da polipose nasossinusal por meio da tomografia computadorizada Evaluation of the concordance between observers in sinunasal polyposis through computed tomographic analysis

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    Elaine A. Mendes

    2004-08-01

    Full Text Available Polipose nasossinusal (PNS é uma entidade de etiologia controversa, caracterizada por uma condição inflamatória da superfície mucosa das fossas nasais e seios paranasais, bilateralmente. A queixa principal do paciente consiste na obstrução nasal e, ao exame físico, observam-se freqüentemente massas polipóides ocupando as cavidades nasais em extensões variáveis. Além da rinoscopia anterior e da endoscopia nasal, o uso da tomografia computadorizada (TC torna-se necessário para avaliação das fossas nasais e da presença ou não do acometimento dos seios paranasais por essas massas, bem como a sua extensão. Este trabalho tem como objetivo avaliar a concordância interobservadores, por meio da análise da tomografia computadorizada, de 32 casos de PNS. FORMA DE ESTUDO: Clínico prospectivo. CASUÍSTICA E MÉTODOS: Foram avaliadas 32 TC de pacientes portadores PNS por dois observadores experientes, separadamente, em relação à presença ou não de 3 sinais tomográficos sugestivos dessa doença: (1 alargamento infundibular do complexo ostiomeatal, (2 abaulamento lateral da lâmina papirácea e (3 apagamento do trabeculado ósseo etmoidal. RESULTADOS: Observou-se Qui-quadrado não significante para o primeiro e segundo sinais (p=0,7055 e p=0,2057 e significante para o terceiro (p=0,0040. Contudo, o coeficiente de correlação de Kendall entre os dois observadores foi significante para os três sinais tomográficos acima citados (pSinonasal polyposis (SNP is a condition with a controversial aethiology, known by bilaterally inflammatory mucous membranes of nasal and paranasal sinuses. The major patient's complaint is nasal obstruction, and polypoid masses in different sizes can be found during nasal cavity examination. Beyond anterior rhinoscophy and nasal endoscopy, screening sinus computed tomography (SSCT is necessary to measure the size and the extent of the polyps into nasal cavities and paranasal sinuses. The purpose of this

  18. Avaliação da reprodutibilidade das medidas da camada de fibras nervosas retiniana e da cabeça do nervo óptico pela tomografia de coerência óptica

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    Ricardo Rau

    2012-10-01

    Full Text Available OBJETIVO: Determinar a reprodutibilidade da espessura da camada de fibras nervosas da retina peripapilar e dos parâmetros da cabeça do nervo óptico em olhos normais, utilizando a tomografia de coerência óptica de domínio espectral (SD-OCT. MÉTODOS: Trinta e quatro olhos de 34 indivíduos saudáveis foram incluídos no estudo. O protocolo do cubo do disco óptico 200x200 do OCT Cirrus foi utilizado para gerar 3 imagens de cada olho para avaliar a reprodutibilidade. O coeficiente de correlação intraclasse (ICC foi calculado para as medidas da espessura da camada de fibras nervosas da retina e da cabeça do nervo óptico. RESULTADOS: A correlação foi excelente para todas as medidas da espessura da camada de fibras nervosas da retina (ICC entre 0,87 e 0,98. O mesmo ocorreu com os parâmetros da cabeça do nervo óptico que, com exceção da razão E/D vertical (ICC 0,56, apresentou ICC entre 0,83 e 0,99. CONCLUSÃO: As medidas de espessura da camada de fibras nervosas da retina peripapilar e os parâmetros da cabeça no nervo óptico demonstraram uma excelente reprodutibilidade com o OCT Cirrus, indicando que este aparelho poderá ser uma ferramenta útil no estudo do glaucoma. Este estudo apresenta algumas limitações, como o pequeno número de casos avaliados, sendo necessários maiores estudos para corroborar nossos achados.

  19. Suburban amoebiasis. CT and US findings and percutaneous treatment of amoebic liver abscess; Amebiasi sub-urbana: aspetti diagnostici con tomografia computerizzata ed ecografia e trattamento percutaneo degli ascessi amebici del fegato

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    Salzano, A.; De Rosa, A. [Ospedale Loreto Mare, Naples (Italy). Servizio di Radiologia; Rossi, E.; Carbone, M.; Mondillo, F. [Naples Univ. II, Naples (Italy).Dipt. di Scienze Biomorfologiche e Funzionali, Servizio di Diagnostica per Immagini; Tuccillo, M. [Azienda Ospedaliera di Rilievo Nazionale A. Cardarelli, Naples (Italy). Servizio di Radiologia; Capuano, N. [Ospedale Loreto Mare, Naples (Italy). Div. di Chirurgia; Nunziata, A. [Naples Univ. II, Naples (Italy). Ist. di Radiologia

    2000-03-01

    The study reports ultrasonography and computerise tomography findings in 16 patients with amoebic abscesses, 12 of whom lived in a temperate peripheral area north-east of Naples (Italy). All patients have a clinical-diagnostic condition called sub-urban amoebiasis. The personal experience with the US guided therapeutic drainage of amoebic abscess with repeated cavity washing, which is important for positive parasitology. Combined US and CT assessment facilitated the diagnosis of amoebiasis and its differentiation from pyogenic abscess and hepatoma. [Italian] La colonizzazione epatica rappresenta la localizzazione piu' comune dell'amebiasi extraintestinale e gli ascessi epatici ne costituiscono la manifestazione piu' frequente sviluppandosi nel 3-9 % dei pazienti affetti da infezione parassitaria. Diversi studi confermano che la terapia medica dell'amebiasi risulta piu' efficace quando viene associato il drenaggio percutaneo degli ascessi epatici con piu' rapida guarigione clinica e risposta favorevole dell'organismo. Scopo del presente lavoro e' di descrivere gli aspetti ecografici e di tomografia computerizzata degli ascessi amebici in un gruppo di 16 pazienti, 12 dei quali residenti in zona temperata e periferica di una vasta area a nord-est di Napoli presentandosi con caratteristico e raro quadro clinico-diagnostico definito amebiasi sub-urbana. Si discute infine l'esperienza personale del drenaggio terapeutico sotto guida ecografica dell'ascesso con tecnica del lavaggio ripetuto dalla cavita', importante ai fini della positivita' dell'esame. L'associazione dei reperti tipici ecografici e TC ha consentito la diagnosi agevole dell'amebiasi differenziandola dall'ascesso piogenico e dall'epatoma.

  20. Detection of beetle damage in forests by X-ray CT image processing Detecção de danos causados por besouro em florestas com processamento de imagens de tomografia computadorizada de raios X

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    Paulo Estevão Cruvinel

    2003-10-01

    Full Text Available Some beetle species can have devastating economic impacts on forest and nursery industries. A recent example is Anophophora glabripennis, a species of beetle known in the United States as the ''Asian Longhorrned beetle'', which has damaged many American forests, and is a threat which can unintentionally reach south American countries, including Brazil. This work presents a new method based on X-ray computerized tomography (CT and image processing for beetle injury detection in forests. Its results show a set of images with correct identification of the location of beetles in living trees as well as damage evaluation with time.Algumas espécies de besouros têm elevado impacto econômico em florestas e indústrias de móveis. Exemplo recente é aquele produzido pelo besouro Anophophora glabripennis, uma espécie conhecida nos Estados Unidos como Asian Longhorn, que tem produzido danos significativos em várias florestas americanas, representando uma ameaça que poderá encontrar transporte não-intencional para países da América do Sul, inclusive para o Brasil. Neste trabalho é apresentado um novo método com base no uso de tomografia de raios X computadorizada (CT e processamento de imagens digitais para detecção de injúrias causadas por besouros em florestas. Os resultados mostram a correta identificação da localização de besouros em árvores vivas, como também fornecem uma avaliação do estrago temporal causado.

  1. Contribuição da tomografia de coerência óptica de 820 nm na distrofia granular corneana: relato de caso Contribution of 820 nm optical coherence tomography in granular corneal dystrophy: case report

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    Beatriz de Abreu Fiuza Gomes

    2008-10-01

    Full Text Available O objetivo deste trabalho é correlacionar os dados clínicos de um caso de distrofia granular com o exame de tomografia de coerência óptica (OCT de 820 nm de modo a determinar o nível intra-estromal dos depósitos corneanos. É relatado um caso de distrofia granular em paciente de 38 anos do sexo masculino. Foi realizado exame oftalmológico completo e OCT para documentação do caso. O aparelho utilizado foi o Stratus OCT III, originalmente desenvolvido para avaliação do segmento posterior. A acuidade visual corrigida foi de 20/50 em ambos os olhos. À biomicroscopia, foram observadas opacidades em "floco de neve" em diferentes níveis do estroma corneano bilateral e de forma simétrica. A avaliação pelo OCT revelou múltiplos pontos hiperreflectivos nas camadas superficiais e profundas do estroma. Foi possível acessar a anatomia morfológica da córnea através de cortes seriados realizados pelo Stratus OCT III e confirmar a profundidade dos depósitos corneanos.The purpose of this case report is to correlate clinical features of granular dystrophy using 820 nm optical coherence tomography (OCT in order to determine the depth of intrastromal corneal deposits. We report a case of a 38-year-old man with granular dystrophy. After complete ophthalmologic examination the patient was submitted to OCT, using the Stratus OCT III, originally proposed for studying disorders of the posterior segment. Best-corrected visual acuity was 20/50 in both eyes. Biomicroscopy revealed bilateral "snowflake"opacities in different levels of the stromal layer. OCT disclosed multiple hiperreflective dots in anterior and deeper stromal layers. It was possible to assess the morphology of the cornea and to determine the depth of the corneal deposits with serial cross-sectional OCT scans using the Stratus OCT III.

  2. Tomografia por emissão de pósitrons com FDG-18F na avaliação de pacientes com artrite reumatoide – revisão sistemática

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    Dalton Alexandre dos Anjos

    2014-12-01

    Full Text Available Introdução A artrite reumatoide (AR é uma doença caracterizada pela inflamação da membrana sinovial. Diversos autores têm investigado o papel da tomografia por emissão de pósitrons (PET com flúor-18 (FDG-18F na AR. Objetivos Revisão sistemática da literatura atual sobre o papel do PET com FDG-18F no diagnóstico, determinação da atividade da doença e avaliação da resposta ao tratamento em pacientes com AR. Métodos Foram realizadas buscas nas bases de dados Medline, Biblioteca Cochrane, Lilacs, Pubmed e Scopus nos idiomas português, inglês e espanhol, utilizando as palavras-chave «artrite reumatoide», «sinovite», «FDG», «PET», «metabolismo glicolítico» e «atividade da doença». Resultados 142 artigos foram inicialmente identificados, dos quais apenas 40 relacionavam-se diretamente ao tema. Foram selecionados 12 artigos originais e três relatos de caso que preenchiam os critérios de inclusão. Discussão A presença de fibroblastos e macrófagos ativados no pannus é responsável pela intensa captação periarticular de FDG-18F. Os padrões de captação não permitem o diagnóstico diferencial com outras artrites. A intensidade de captação e o número de articulações envolvidas são parâmetros metabólicos de atividade da doença que apresentam boa correlação com os índices compostos. Estudos longitudinais de PET têm se mostrado úteis na avaliação da resposta ao tratamento com anti-TNF. Quando realizado precocemente, PET pode predizer a resposta terapêutica. Conclusão Embora o real papel dessa nova técnica na investigação da AR ainda não esteja estabelecido, PET com FDG-18F é uma ferramenta promissora na determinação da atividade e na predição de resposta ao tratamento de pacientes com AR.

  3. Neoplasias pulmonares difusas em pacientes com a síndrome de imunodeficiência adquirida Correlação da tomografia computadorizada de alta resolução com a anatomopatologia

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    Edson Marchiori

    2002-03-01

    Full Text Available RESUMO: Neste artigo foram discutidos os principais aspectos tomográficos das neoplasias pulmonares difusas que acometem o paciente com a síndrome da imunodeficiência adquirida. Com este objetivo foram revistas as tomografias computorizadas de alta resolução de 8 pacientes, 4 deles com linfomas do tipo não-Hodgkin e 4 com sarcoma de Kaposi, e feita correlação com os achados anatomo-patológicos. O principal aspecto observado foi a disseminação linfática, determinando espessamen-to das bainhas broncovasculares, dos septos interlobulares e da superfície pleural. Em ambas as doenças tal aspecto deveu-se à infiltração destes compartimentos pelas células neoplásicas. Outros aspectos observados foram os nódulos de limites mal definidos no sarcoma de Kaposi, e múltiplos nódulos com broncograma aéreo, e consolidação parenquimatosa, nos linfomas. Derrames pleurais foram detectados em ambas as doenças.REV PORT PNEUMOL 2002; VIII (2: ABSTRACT: In this article we discuss the main computed tomographic aspects of diffuse pulmonary neoplasias in AIDS patients. For this purpose we reviewed the High Resolution CT of eight patients, four of them with Non-Hodgkin Lymphoma, and four with Kaposi’s sarcoma, and correlated with anatomopathologic findings. The main finding was lymphatic spread which produces peribronchovascular, septal interlobular and pleural thickening. In both diseases this aspects were caused by neoplastic cells infiltration of these compartments. Other findings includes ill defined nodules in Kaposi’s sarcoma and multiple nodules with air-bronchograms and parenchymal consolidations in lymphomas. Pleural effusions were seen in both diseases.REV PORT PNEUMOL 2002; VIII (2: Palavras-chave: SIDA, pulmões, TCAR, anatomopatologia, sarcoma de Kaposi, linfomas, Key-words: AIDS, lungs, HRCT, anatomopathology, Kaposi’s sarcoma, lymphoma

  4. Biópsia percutânea de lesões ósseas guiada por tomografia computadorizada: taxas de definição diagnóstica e complicações

    Directory of Open Access Journals (Sweden)

    Macello Jose Sampaio Maciel

    2014-10-01

    Full Text Available Objetivo: Determinar taxas de definição diagnóstica e complicações da biópsia percutânea guiada por tomografia computadorizada (TC de lesões ósseas suspeitas de malignidade. Materiais e Métodos: Estudo retrospectivo que incluiu 186 casos de biópsia percutânea guiada por TC de lesões ósseas no período de janeiro de 2010 a dezembro de 2012. Todas as amostras foram obtidas usando agulhas de 8 a 10 gauge. Foram coletados dados demográficos, história de neoplasia maligna prévia, dados relacionados à lesão, ao procedimento e ao resultado histológico. Resultados: A maioria dos pacientes era do sexo feminino (57% e a idade média foi 53,0 ± 16,4 anos. Em 139 casos (74,6% a suspeita diagnóstica era metástase e os tumores primários mais comuns foram de mama (32,1% e próstata (11,8%. Os ossos mais envolvidos foram coluna vertebral (36,0%, bacia (32,8% e ossos longos (18,3%. Houve complicações em apenas três pacientes (1,6%, incluindo uma fratura, um caso de parestesia com comprometimento funcional e uma quebra da agulha necessitando remoção cirúrgica. Amostras de 183 lesões (98,4% foram consideradas adequadas para diagnóstico. Resultados malignos foram mais frequentes nos pacientes com suspeita de lesão secundária e história de neoplasia maligna conhecida (p < 0,001 e nos procedimentos orientados pela PET/CT (p = 0,011. Conclusão: A biópsia percutânea guiada por TC é segura e eficaz no diagnóstico de lesões ósseas suspeitas.

  5. Calcificação nos núcleos da base na tomografia computadorizada: correlação clínica em 25 pacientes consecutivos Basal ganglia calcification on computed tomography: clinical characteristics in 25 patients

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    Glória Maria A.S. Tedrus

    2006-03-01

    Full Text Available Analisamos os aspectos clínicos de 25 pacientes consecutivos que apresentaram calcificação nos núcleos da base na tomografia computadorizada (TC de crânio. Esta ocorreu em 0,68% de todos os exames realizados no período. Vinte e três pacientes apresentavam condições clínicas diversas, a saber: cefaléia em 7 casos, acidente vascular cerebral em 5, síndrome extrapiramidal em 2, processo expansivo cerebral em 2, epilepsia, retardo do desenvolvimento neuropsicomotor, demência e trauma de crânio em um caso cada ou outras condições neurológicas em 3. Não havia sintomas neurológicos em 2 casos. Em 15 pacientes (60,0% havia, além da calcificação dos núcleos da base, outras alterações na TC. Correlação clínica foi observada apenas com as outras alterações da TC e não com a calcificação dos núcleos da base, corroborando a hipótese de que esta possa ser um achado incidental.Twenty-five patients presenting basal ganglia calcification were assessed. This finding comprised 0.68% of all skull CT scan carried out during the period. Two patients were neurologically asymptomatic and 23 presented a variety neurological disorders - headache (7 patients, stroke (5 patients, extrapyramidal syndromes (2 patients, tumor (2 patients, epilepsy (1 patient, mental retardation (1 patient, dementia (1 patient, cranial trauma (1 patient, other neurological conditions (3 patients - or were asymptomatic from the neurological point of view (2 patients. Findings in the CT scan other than the basal ganglia calcification were observed in 15 (60% patients. There was a clinical-CT scan correlation in these cases but not in those in which the basal ganglia calcification was an isolated finding. This study highlights the fact that basal ganglia calcification is often a nonspecific finding on CT scan and that it may not be possible to establish a clinical-pathological correlation between them.

  6. Tuberculose pulmonar: achados na tomografia computadorizada de alta resolução do tórax em pacientes com doença em atividade comprovada bacteriologicamente Pulmonary tuberculosis: findings on high resolution computerized tomography of active disease on patients with bacteriological confirmation

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    CRISTIANE ALÓ CAMPOS

    2002-01-01

    Full Text Available Objetivo: Descrever os achados em pacientes com tuberculose pulmonar em atividade na tomografia computadorizada de alta resolução e o padrão de distribuição das lesões pelo parênquima pulmonar. Casuística e método: Foram analisadas retrospectivamente as tomografias de alta resolução de 42 pacientes com diagnóstico bacteriológico de tuberculose pulmonar ou forte suspeita clínica, com posterior confirmação bacteriológica. Resultados: Os principais sinais sugestivos de atividade encontrados foram nódulos do espaço aéreo (83%, nódulos centrolobulares (74%, aspecto de árvore em brotamento (67%, cavitações (67%, espessamento das paredes brônquicas (55%, consolidações (48%, opacidade em vidro fosco (21%, e espessamento do interstício pulmonar (9%. Conclusão: A tomografia computadorizada de alta resolução do tórax pode sugerir fortemente atividade da doença, sendo particularmente útil nos pacientes com baciloscopias negativas e/ou radiografias indeterminadas, permitindo a instituição de tratamento adequado, antes mesmo do crescimento da micobactéria em meio de cultura.Background: The aim of this study was to describe the signs of active tuberculosis in patients submitted to high resolution computerized tomography and the distribution of lesions along the pulmonary parenchyma. Material and methods: The high resolution CTs performed on 42 patients with tuberculosis either bacteriologically diagnosed or clinical suspected and later confirmed by bacteriological tests were studied. Results: The signs of disease activity observed were airspace nodule (83%, centrilobular nodule (74%, tree-in-bud pattern (67%, cavitations (67%, bronchial thickening (55%, parenchymal consolidations (48%, ground glass opacity (21% and thickening of the inter and intralobular septa (9%. Conclusion: High resolution computed tomography can be strongly suggestive of disease activity, is particularly helpful in patients with negative smear and

  7. Influence of the interplay between helicoidal magnetic ordering and ...

    Indian Academy of Sciences (India)

    ordering and superconductivity on the differential conductance in ... carbide compounds are motivated by the possibility of a detailed investigation of the anisotropy of .... The last equation corresponds to the usual BCS self-consistent ... the actual electron–phonon interaction λ and its effective value, we can expand quanti-.

  8. Densidade de um planossolo sob sistemas de cultivo avaliada por meio da tomografia computadorizada de raios gama Bulk density of an alfisol under cultivation systems in a long-term experiment evaluated with gamma ray computed tomography

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    Adilson Luís Bamberg

    2009-10-01

    Full Text Available A sustentabilidade do arroz (Oryza sativa L. irrigado em solos de várzea está alicerçada na utilização da rotação e sucessão de culturas, fundamentais para o controle do arroz-vermelho e preto. Os reflexos sobre os atributos dos solos de várzea merecem estudos em especial sobre a compactação do solo. O objetivo deste trabalho foi identificar camadas compactadas em Planossolo submetido a diferentes sistemas de cultivo e preparo, avaliando-se a densidade do solo (Ds pela Tomografia Computadorizada de Raios Gama (TC. A análise foi realizada em um experimento de longa duração, conduzido de 1985 a 2004, na Estação Experimental da Embrapa Clima Temperado, Capão do Leão, RS, num delineamento experimental em blocos ao acaso, com sete tratamentos, cada um com quatro repetições (T1 - um ano de arroz com preparo convencional do solo seguido de dois anos de pousio; T2 - cultivo contínuo de arroz com preparo convencional do solo; T4 - rotação de arroz e soja (Glycine max L. com preparo convencional do solo; T5 - rotação de arroz, soja e milho (Zea maiz L. em preparo convencional do solo; T6 - plantio direto de arroz no verão em sucessão do azevém (Lolium multiflorum L. no inverno; T7 - rotação de arroz sob plantio direto e soja sob preparo convencional do solo; T8 - testemunha: solo sem cultivo. A Tomografia Computadorizada de Raios Gama permitiu detectar que o plantio direto de arroz no verão em sucessão do azevém no inverno não resultou na formação de camadas compactadas; a utilização de dois anos de pousio, no sistema de produção de arroz irrigado, não foi suficiente para evitar a formação de uma camada superficial compactada; e a rotação de arroz, soja e milho com preparo convencional do solo apresentou duas camadas compactadas (0,0 a 1,5 cm e 11 a 14 cm, indicando que essas podem limitar a produção agrícola nesse sistema de produção em Planossolos.The sustainability of irrigated rice (Oryza sativa L. in

  9. Prevalence of soft tissue calcifications in cone beam computed tomography images of the mandible = Prevalência de calcificações em tecido mole na região mandibular avaliadas por dois sistemas de tomografia computadorizada por feixe cônico

    OpenAIRE

    Nunes, Leiliane Ferreira da Silva

    2011-01-01

    Objetivo: Determinar a prevalência de calcificações em tecido mole na região mandibular por meio de análise de imagens axiais provenientes de dois sistemas de tomografia computadorizada por feixe cônico (TCFC), NewTom 3G® e Classic i-Cat® Método: Foram avaliadas 246 imagens da região mandibular. Destas, 163 foram adquiridas no aparelho NewTom 3G® e 83 no aparelho Classic i-Cat®. A análise estatística foi baseada no teste exato de Fisher e no teste Qui-quadrado para comparação das proporçõe...

  10. Análise das variações morfológicas da ATM em pacientes com artrite reumatóide através de tomografia computadorizada = Analysis of the morphologyc variations in the TMJ the patients with rheumatoid arthritis through the computer tomography

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    Vasconcelos, Belmiro Cavalcanti do Egito

    2005-01-01

    Full Text Available Realizou-se um estudo qualitativo e quantitativo enfocando as alterações morfométricas da articulação temporomandibular (ATM, em pacientes com o diagnóstico de artrite reumatóide (AR por meio de tomografia computadorizada. Foram analisados 6 casos onde são descritas as alterações estruturais dos componentes ósseos de 12 ATMs. Os resultados indicaram que todas as ATMs apresentaram alterações, sendo as alterações mais freqüentes a esclerose óssea subcondral, seguida do aplainamento da eminência articular. Todos os pacientes apresentaram distúrbio de mobilidade

  11. Anatomic considerations for C2 pedicle screw placement: the use of computerized tomography measurements Consideraciones anatómicas de la cocalización de los tornillos pediculares en C2: uitlización de las medidas de la tomografia computadorizada Considerações anatômicas sobre a localização dos parafusos pediculares em C2: utilização das medidas da tomografia computadorizada

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    Adebukoa Onibokun

    2009-03-01

    eje del pedículo y el ángulo transverso del pedículo (ángulo entre el eje del pedículo y la línea media del cuerpo vertebral. RESULTADOS: el valor promedio del ancho pedicular fue de 5.8 1.2mm. En el sexo masculino el valor promedio del ancho del pedículo (6.0 1.3mm fue mayor comparado con el sexo femenino (5.6 1.1mm, sin embargo no fue observada una diferencia estadística. El valor promedio del ángulo transverso del pedículo fue de 43.9 3.9 grados, siendo de 43.2 3.8 grados en el sexo masculino y 44.7 3.7 grados en el sexo femenino. CONCLUSIÓN: la proyección y determinación en el periodo preoperatorio de las dimensiones anatómicas del pedículo C2 son importantes para la determinación de la trayectoria y dimensiones del local donde el implante será colocado.OBJETIVO: o conhecimento detalhado das características anatômicas do pedículo de C2 é necessário para minimizar os riscos relacionados com a colocação dos parafusos. O objetivo deste trabalho é avaliar as medidas lineares e angulares do eixo axial verdadeiro do pedículo de C2 utilizando tomografia computadorizada. MÉTODOS: foram utilizadas tomografias computadorizadas axiais de 93 pacientes (47 do sexo masculino e 46 do sexo feminino com média de idade de 48 anos. As imagens axiais do pedículo de C2 foram selecionadas para o estudo e os parâmetros estudados foram: largura do pedículo (diâmetro mediolateral do istmo do pedículo perpendicular ao eixo do pedículo e o ângulo tranverso do pedículo (ângulo entre o eixo do pedículo e a linha média do corpo vertebral. RESULTADOS: o valor médio da largura do pedículo foi 5,81,2mm. Nos pacientes de sexo masculino o valor médio da largura do pedículo (6,01,3mm foi maior que nos pacientes de sexo feminino (5,61,1mm. No entanto, não foi observada diferença estatística. O valor médio do ângulo transverso do pedículo foi de 43,93,9 graus, sendo de 43,23,8 graus no sexo masculino e 44,73,7 graus no sexo feminino. CONCLUSÃO: o

  12. Correlação entre hipótese diagnóstica e laudo de tomografia axial computadorizada craniana Correlation between diagnostic hypothesis and result of cranial computed axial tomography

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    Edison Matos Nóvak

    2001-09-01

    Full Text Available Para avaliar a utilização da tomografia axial computadorizada craniana (TC em nosso meio, analisamos as solicitações de 367 exames consecutivos no período compreendido entre 07/1995 e 07/1996. Houve ampla variação da faixa etária, com média de 31,7 ± 22,9 anos. As especialidades que mais solicitaram o exame foram: Neurologia (36,2%, Pronto Atendimento (17,4%, Neuropediatria (16,9% e Clínica Médica (5,9%. As indicações mais frequentes para o exame foram: convulsão (30%, cefaléia (26,2%, déficit motor (20,2% e redução do nível de consciência (16,9%. As "hipóteses" aventadas com maior frequência foram: afastar lesão estrutural (9,0%, acidente vascular não discriminado (8,2% e neurocisticercose (8,2%. O laudo da TC foi normal em 50,4% dos exames. Os laudos anormais mais frequentes foram: hidrocefalia (5,4%, acidente vascular isquêmico (5,4% e neoplasia (3,5%. As maiores taxas de achados normais foram encontradas nas "hipóteses" de cefaléia (94,4%, convulsão (71,4% e afastar lesão estrutural (66,7%. Os maiores índices de acerto entre hipótese e laudo foram encontrados nas situações de "afastar lesões estruturais" (66,7%, hidrocefalia (50%, acidente vascular cerebral isquêmico (50% e hematoma (50%. Concluimos que a utilização de um recurso auxiliar de diagnóstico como a TC cumpre melhor ainda a sua função se o requisitante do exame preencher com clareza e detalhamento o pedido do exame.The use of computed axial tomography (CT in the investigation of neurologic disorders is attractive for his disponibility in the health services. However, the indications of the exam and the correlation with the clinical features has not been frequently studied. We study correlation between the requests of CT and the findings reported by the radiologist, in 367 exams performed from 07/1995 to 07/ 1996. The mean age was 31.7 ± 22.9 years. The CT were requested in decrescent order of frequency by the Services of Neurology (36

  13. Computed tomography scan of the head in patients with migraine or tension-type headache Tomografia computadorizada do crânio em pacientes com migrânea ou cefaléia tensional

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    Marcelo Moraes Valença

    2002-09-01

    Full Text Available A retrospective study was performed in order to evaluate the frequency of abnormalities found by computed tomography (CT scan of the head in 78 patients with migraine or tension-type headache. In the present study CT scan was normal in 61.5% of the patients with migraine or tension-type headache. A number of abnormalities were encountered in more than one third of the patients studied, including inflammatory sinus disease (19.2%, cysticercosis (3.9%, unruptuted cerebral aneurysm (2.6%, basilar impression (2.6%, intracranial lipoma (2.6%, arachnoid cyst (2.6%, empty sella (2.6%, intracranial neoplasm (2.6%, and others (2.6%. None of these lesions were symptomatic or responsible by the headache picture, therefore, considered incidental findings. In conclusion, the fortuitous encounter of some abnormalities on CT scan of the head is often higher than what we could predict in patients suffering migraine or tension-type headache. We briefly discuss clinical, epidemiologic, and practical management of some of the abnormalities detected by CT scan as well as the indication to request a neuroimaging investigation.Um estudo retrospectivo foi realizado visando avaliar a frequência de anormalidades encontradas durante a realização de estudo por tomografia computadorizada (TC em 78 pacientes com migrânea ou cefaléia do tipo tensional. A TC foi normal em 61,5% dos pacientes examinados. Em um terço dos pacientes estudados foram detectadas anormalidades, como doença inflamatória dos seios paranasais (19,2%, cisticercose (3,9%, aneurisma cerebral não-roto (2,6%, impressão basilar (2,6%, lipoma intracraniano (2,6%, cisto aracnoideo (2,6%, sela vazia (2,6%, neoplasia intracraniana (2,6% e outras afecções (2,6%. Nenhuma destas lesões era sintomática (achado incidental. Concluindo, o encontro fortuito de algumas anormalidades na TC é frequentemente mais elevado do que se prediz em pacientes com cefaléia primária. Nós discutimos brevemente alguns

  14. Application of the axial tomography computed for the detection of bags of dampness in dry wood of Gmelina arborea (Roxb.); Aplicacion de la tomografia axial computarizada para la deteccion de bolsas de humedad en madera seca de Gmelina arborea (Roxb.)

    Energy Technology Data Exchange (ETDEWEB)

    Moya R, Roger; Munoz A, Freddy [Inst. Tecnologico de Costa Rica, Escuela de Ingenieria Forestal, Apdo. 159-7050, Cartago 7050(Costa Rica); Escalante, Ivan [Clinica Santa Fe, San Jose (Costa Rica)

    2006-07-01

    detectar y establecer los limites de la presencia de humedad en la madera de Gmelina arborea al lado de la exploracion de tomografia computarizada (CT-escaner), una tecnica aplicada en el diagnostico medico. Junto con las bolsas humedas, en la CT-del escaner se presentan imagenes de color gris y con valores bajos de la Unidad Hounsfield (UH) o numero CT. Cuando estos valores fueron transformados a la densidad de la madera, se determino que las bolsas humedas estaban a una densidad de unos 190 kg/m{sup 3}, un valor superior al normal de la madera. Ademas, fue posible observar el crecimiento de anillos de arboles en la CT-del escaneo de imagenes, una caracteristica importante para la investigacion dendrocronologica. Los resultados obtenidos permitieron demostrar que es posible aplicar esta tecnica en el proceso de produccion de madera, para detectar las zonas con un alto MC en el secado de la madera de Gmelina arborea. (autor)

  15. Frequency of suspected cases of neurocysticercosis detected by computed skull tomography in Santa Maria, RS, Brazil Freqüência de casos suspeitos de neurocisticercose em tomografias computadorizadas de crânio em Santa Maria, RS, Brasil

    Directory of Open Access Journals (Sweden)

    José Edson Paz da SILVA

    2000-02-01

    Full Text Available Due to the lack of studies about neurocysticercosis in the South of Brazil, an investigation was conducted to determine the percentage of suspected cases of neurocysticercosis in computed tomography diagnoses in Santa Maria, RS, from January 1997 to December 1998. Of 6300 computed tomographies (CT of the skull performed at the private Hospital de Caridade Astrogildo de Azevedo, 80, i.e., 1.27% were suspected of neurocysticercosis. Fifty were women (62.5% and 30 were men (37.5%. The most frequent radiological manifestation indicating neurocysticercosis was the presence of calcifications (isolated or associated, with a 95% rate (76 cases, while the presence of hypodense lesions reached a 5% rate (4 cases. After routine analysis, each CT was evaluated again and the suspected cases were confirmed. The percentage of suspected cases of neurocysticercosis detected by CT in the present study carried out in Santa Maria was considered low (1.27%. This can be explained by the fact that tomography is not accessible to the economically underprivileged population of Santa Maria. We hope that the present study can alert the population and the professionals to the fact that neurocysticercosis is a more frequent disease than indicated by the few diagnoses made.Com o objetivo de iniciar um estudo sobre a neurocisticercose no Sul do Brasil, foi verificada a porcentagem de casos suspeitos de neurocisticercose em tomografia computadorizada de crânio (TCC em Santa Maria, entre janeiro de 1997 e dezembro de 1998. Os resultados mostraram que entre 6300 TCC realizadas no Hospital de Caridade Astrogildo de Azevedo, 80, isto é, 1,27% eram suspeitas de neurocisticercose. Constatamos que 50 eram mulheres (62,5% e 30 homens (37,5%. A manifestação radiológica mais freqüente para indicar neurocisticercose foi a calcificação (isolada ou associada com 95% (76 casos, enquanto a presença de lesões hipodensas foi de 5% (4 casos. Após a análise de rotina cada TCC foi

  16. Validation of computed tomography protocols for simulated mandibular lesions: a comparison study Validação de protocolos de tomografia computadorizada para lesões simuladas em mandíbula: estudo comparativo

    Directory of Open Access Journals (Sweden)

    Andréia Perrella

    2007-06-01

    Full Text Available Computed tomography is the choice technique to assess oral and maxillofacial osseous lesions because it provides hard and soft tissues visualization in one examination without superimposition of surrounding structures. This examination offers a significant advance in maxillofacial lesions detection with an excellent anatomic resolution. The aim of this research was to evaluate the validity of two protocols, in axial sections, in simulated mandibular lesions. Two CT protocols were obtained in dry mandibles in which perforations were done simulating lesions. Two observers, previously calibrated, evaluated the images according to different parameters. The results indicated that the sensitivity and specificity in lesion detection were 100% for both protocols, but the detection of loci number of multilocular lesions and the location and detection of medullar invasion obtained reduced validity values, which were influenced by the acquisition protocol. We concluded that thinner axial slices and reconstructions were more effective in detecting early medullar invasion and loci number. Thicker protocols were not considered appropriate to detect multilocular lesions and early stages of medullar invasion.A tomografia Computadorizada é a técnica de escolha no exame de lesões ósseas orais e maxilo-faciais porque proporciona a visualização de tecidos duros e moles em aquisição única e sem sobreposição de estruturas adjacentes. Este exame oferece um avanço significativo na detecção de lesões maxilo-faciais, com excelente resolução anatômica. O objetivo desta pesquisa foi avaliar a validade de dois protocolos, em secções axiais, em lesões simuladas de mandíbula. Dois protocolos de TC foram obtidos em mandíbulas secas em que foram feitas perfurações, simulando lesões. Dois observadores previamente calibrados avaliaram as imagens seguindo parâmetros diversos. Como resultados pudemos observar que a sensibilidade e a especificidade foram

  17. Características estruturais maculares de olhos de pré-escolares nascidos prematuros: análise por tomografia de coerência óptica e oftalmoscopia binocular indireta

    Directory of Open Access Journals (Sweden)

    Lígia Beatriz Bonotto

    2013-04-01

    Full Text Available OBJETIVO: Comparar a estrutura retiniana da mácula e fóvea entre prematuros com retinopatia da prematuridade (ROP estágios II e III pós-tratamento, com ROP estágios II e III regredida espontaneamente e sem ROP, através de exames de tomografia de coerência óptica (OCT e da oftalmoscopia binocular indireta (OBI. MÉTODOS: Estudo do tipo transversal, observacional e não cego. Foram incluídas crianças prematuras nascidas entre 06/1992 e 06/2006 e examinadas entre 06/2009 e 12/2010; idade gestacional menor ou igual a 32 semanas e peso ao nascer menor ou igual a 1.599 g; com mínimo de três consultas durante o período de seleção; sem retinopatia da prematuridade ou com diagnóstico de ROP estágios II ou III em pelo menos um dos olhos com regressão espontânea ou após tratamento; máximo de seis meses de idade cronológica para o primeiro exame no serviço; idade cronológica mínima de quatro anos no período da reavaliação. Foram excluídas crianças prematuras que não compareceram ou que não tinham condições clínicas para a realização dos exames de reavaliação. Os prematuros foram divididos em três grupos: G1- com ROP pós-tratamento; G2- com ROP pós-regressão espontânea; e G3- sem ROP. Os exames realizados foram OBI e OCT. RESULTADOS: Vinte e quatro prematuros (48 olhos apresentaram os critérios exigidos para a pesquisa, com idade média cronológica entre 5 e 6 anos. À OBI, houve diferença estatística significativa para a presença de alterações na retina dos prematuros do grupo G1. No entanto estas alterações corresponderam às lesões cicatriciais deixadas pelo tratamento da ROP, sem comprometimento visível da região macular. À OCT houve diferença estatística significativa para a maior espessura foveal para os prematuros do grupo G1. Considerando-se o olho esquerdo, não houve diferença estatística significativa relacionada à espessura da fóvea entre G1 e G3. Não houve diferença entre os tr

  18. Retinal thickness measurement and evaluation of natural history of the diabetic macular edema through optical coherence tomography Medida da espessura retiniana e avaliação da história natural do edema macular diabético pela tomografia de coerência óptica

    Directory of Open Access Journals (Sweden)

    Rosana Zacarias Hannouche

    2009-08-01

    influence on the center point thickness data, whereas values of visual acuity were significantly correlated with it. CONCLUSION: This study presents the optical coherence tomography applicability in the detection and semiologic evaluation of diabetic macular edema in patients with visual acuity 20/40 or greater, during one year, showing the retinal thickening in the early stages of diabetic retinopathy. Further, it evidenciated the correlation between the increase in foveal thickness and the reduction in visual acuity. Levels of hemoglobin A1c did not influence the center point thickness data. An early detection of clinically significant macular edema leads us to a redefinition of the real meaning of incipient retinopathy and can prevent further significant reduction of vision.OBJETIVOS: 1 Diagnosticar a presença de edema macular diabético em pacientes com retinopatia diabética e acuidade visual igual ou melhor que 20/40, pela realização do exame de tomografia de coerência óptica, medindo a espessura foveal central, ao longo de um ano. 2 Avaliar a história natural do edema, ao longo de um ano, associando a espessura foveal central com a hemoglobina glicosilada (HbA1c e alterações na acuidade visual. 3 Correlacionar os resultados obtidos com o grupo controle. MÉTODOS: Estudo prospectivo de uma amostra de 30 pacientes, com edema macular diabético e acuidade visual melhor ou igual a 20/40. O estudo contou com 30 olhos como grupo controle. Foram feitas medidas da melhor acuidade visual corrigida, dosagem de hemoglobina glicosilada, biomicroscopia com lente de 78 dioptrias, angiofluoresceinografia e tomografia de coerência óptica. Determinou-se, pelo propósito do estudo, a espessura foveal central como principal variável. Além da estatística descritiva, utilizaram-se testes para análise dos resultados: foi testada a homogeneidade de cada variável pelos testes t-Student, Qui-Quadrado e teste de Tukey; para correlacionar variáveis utilizou-se a análise de

  19. Seismologic study of Los Humeros geothermal field, Puebla, Mexico. Part II: Seismic tomography by attenuation of coda waves (Qc-1) of local earthquakes; Estudio sismologico del campo geotermico de Los Humeros, Puebla, Mexico. Parte II: Tomografia sismica por atenuacion a partir de ondas de coda (Qc-1) de sismos locales

    Energy Technology Data Exchange (ETDEWEB)

    Antayhua, Yanet; Lermo, Javier [Instituto de Ingenieria, Universidad Nacional Autonoma de Mexico, D.F (Mexico); Carlos, Vargas [Departamento de Geociencias, Universidad Nacional de Colombia (Colombia)]. E-mail: jles@pumas.iingen.unam.mx

    2008-07-15

    In the Los Humeros geothermal field, Puebla, seismic tomography has been studied using the attenuation of coda waves (Qc{sup -1}). Ninety-five local earthquakes (Md{<=}3.6) have been used with depths up to 4.0 km registered in the seismic network stations from December 1997 to December 2004. A simple backscattering model was used, filtered in four ranks of frequencies (2, 4, 6, and 8 Hz) and one window of 5 seconds. For the 3D-representation, we used an approximation based on first-order scattering of ellipsoids. The results show that values of Qc for the used frequencies have a frequency dependency shown in the equation: Qc=24{+-}12f{sup 0.86}{+-}{sup 0.06}, where the low values of Qc were observed in the zone of higher seismic and tectonic activity and in the location of injection and production wells. The high values are located in the periphery of the geothermal field. The distribution of the Qc{sup -1} attenuation in 3D and 2D shows the anomalies of high-seismic attenuation are located in the north, south, and southwestern ends of the zone presently under operation, at depths greater than 2.5 km. [Spanish] Para realizar la tomografia sismica por atenuacion de ondas de coda (Qc{sup -1}) en el campo geotermico de Los Humeros, Puebla, se han utilizado 95 sismos locales (Md{<=}3.6) con profundidades hasta 4.0 km, registrados en las estaciones de su red sismica, durante el periodo de diciembre 1997 a diciembre 2004. Se utilizo el modelo de retrodispersion simple, filtrados en cuatro rangos de frecuencias (2, 4, 6, y 8 Hz) y una ventana de 5 segundos. Para la representacion en 3D, se utilizo una aproximacion basada en elipsoides que representan dispersion de primer orden. Los resultados muestran que los valores de Qc para las frecuencias utilizadas tienen una dependencia con la frecuencia de la forma: Qc=24{+-}12f{sup 0.86}{+-}{sup 0.06}, donde los valores bajos de Qc fueron observados en la zona de mayor actividad sismica y en la ubicacion de pozos inyectores y

  20. Computed tomography image of the mediastinal and axillary lymph nodes in clinically sound Rottweilers Imagem por tomografia computadorizada dos linfonodos axilares e mediastinais de cães rottweilers clinicamente saudáveis

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    Ana Carolina B. Fonseca Pinto

    2013-03-01

    smallest diameter of the axillary and mediastinal lymph nodes not surpassed 7mm and 8mm respectively. Their attenuations were equal or smaller than that of musculature in the post contrast scan.A tomografia computadorizada é uma modalidade diagnóstica que possibilita a avaliação detalhada dos linfonodos e que é capaz de detectar mais precocemente alterações envolvendo estas estruturas, que modalidades de imagem como a radiografia e a ultrassonografia. Tendo em vista a escassez de informações na literatura veterinária esta pesquisa objetivou fornecer informações sobre os aspectos tomográficos normais dos linfonodos axilares e mediastinais em cães. Realizou-se o exame tomográfico de 15 cães adultos, machos e fêmeas, da raça Rottweiler, selecionados como clinicamente normais por meio de anamnese, exame físico, hemograma, perfil bioquímico renal e hepático, eletrocardiograma e exame radiográfico do tórax. Após a injeção intravenosa do contraste iodado hidrossolúvel iônico, realizaram-se cortes tomográficos transversais do tórax com 10mm de espessura e 10mm de incremento em um tomógrafo axial. Os exames tomográficos foram avaliados buscando-se identificar os linfonodos axilares e mediastinais. Quando visibilizados, os linfonodos foram mensurados em seu menor eixo e sua atenuação foi comparada com a da musculatura. Foram calculados a média e desvio padrão da idade, do peso, do comprimento dos animais e do menor eixo dos linfonodos axilares e mediastinais. A média de idade dos animais e o desvio padrão foram de 3,87 anos ±2,03, do peso foi de 41,13kg ± 5,12 e do comprimento dos animais foi de 89,61cm ±2,63. Os linfonodos axilares foram visibilizados em 60% dos animais, a média das mensurações dos menores diâmetros e o desvio padrão foi de 3,58mm ±2,02 com valor mínimo de 1mm e máximo de 7mm. Dos 13 linfonodos observados 61,53% apresentaram-se hipoatenuantes comparativamente a musculatura e 30,77% isoatenuantes. Os linfonodos

  1. Sarcoma de Kaposi relacionado à síndrome da imunodeficiência adquirida: características do comprometimento hepático na tomografia computadorizada e na ressonância magnética Kaposi sarcoma related to acquired immunodeficiency syndrome: hepatic findings on computed tomography and magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Daniel Nobrega da Costa

    2008-04-01

    Full Text Available Sarcoma de Kaposi é uma neoplasia associada a condições de imunossupressão que acomete os vasos linfáticos e sanguíneos. É a neoplasia intra-hepática mais comum na síndrome da imunodeficiência adquirida. A tomografia computadorizada e a ressonância magnética revelam múltiplos pequenos nódulos, proeminência e realce dos planos periportais, devido à presença de tecido neoplásico. Os autores descrevem um caso de paciente masculino, de 47 anos de idade, com síndrome da imunodeficiência adquirida e sarcoma de Kaposi disseminado.Kaposi sarcoma is a neoplasm associated with immunosuppressive conditions, and involving blood and lymphatic vessels. It is the most frequent intrahepatic neoplasm in patients with acquired immunodeficiency syndrome. Computed tomography and magnetic resonance imaging demonstrate multiple small nodules, prominence and contrast-enhancement of periportal branches due to the presence of the neoplastic tissue. The authors report a case of a 47-year-old male patient with acquired immunodeficiency syndrome presenting disseminated Kaposi sarcoma.

  2. Tomografia computadorizada como método auxiliar no diagnóstico e tratamento de lesões intra-ósseas: caso clínico de odontoma composto = Computed tomography as auxiliary method in the diagnostic and treatment of intra-osseos lesions: a case of compound odontoma

    Directory of Open Access Journals (Sweden)

    Paiano, Grasiela Antunes

    2006-01-01

    Full Text Available O advento da tomografia computadorizada (TC possibilita de visualização tridimensional, favorece o diagnóstico e proporcionando um tratamento mais preciso em virtude da localização exata da lesão e análise da proximidade com as estruturas anatômicas vitais relacionadas. Contudo o tratamento de lesões ósseas se torna mais segura, reduzindo o risco de lesão a dentes adjacentes e nervos. O Odontoma é considerado o tumor odontogênico que mais comumente acomete os ossos maxilares. A variante composta deste tumor apresenta a característica de muitas estruturas semelhantes a dentes envolvidas por um halo radiolúcido e grande freqüência na região anterior da maxila, porém o diagnóstico deste tumor nas demais localizações dos maxilares é pouco freqüente. Apresenta normalmente crescimento limitado e expande as corticais ósseas, porém sem tendência à recidiva. O tratamento do odontoma consiste na sua excisão cirúrgica. Os autores pretendem relatar a utilização da TC como método auxiliar no diagnóstico e tratamento de um caso de exérese de um odontoma composto na região anterior da mandíbula

  3. Padronização de um método para mensuração das tábuas ósseas vestibular e lingual dos maxilares na Tomografia Computadorizada de Feixe Cônico (Cone Beam Methodology standardization for measuring buccal and lingual alveolar bone plates using Cone Beam Computed Tomography

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    Marcos Cezar Ferreira

    2010-02-01

    Full Text Available INTRODUÇÃO: a espessura das tábuas ósseas que recobrem os dentes por vestibular e lingual constitui um dos fatores limitantes da movimentação dentária. O avanço tecnológico em Imaginologia permitiu avaliar detalhadamente essas regiões anatômicas por meio da utilização da tomografia computadorizada de feixe cônico (TCFC. OBJETIVO: descrever e padronizar, pormenorizadamente, um método para mensuração das tábuas ósseas vestibular e lingual dos maxilares nas imagens de tomografia computadorizada de feixe cônico. METODOLOGIA: a padronização digital da posição da imagem da face deve constituir o primeiro passo antes da seleção dos cortes de TCFC. Dois cortes axiais de cada maxilar foram empregados para a mensuração da espessura do osso alveolar vestibular e lingual. Utilizou-se como referência a junção cemento-esmalte dos primeiros molares permanentes, tanto na arcada superior quanto na inferior. RESULTADOS: cortes axiais paralelos ao plano palatino foram indicados para avaliação quantitativa do osso alveolar na maxila. Na arcada inferior, os cortes axiais devem ser paralelos ao plano oclusal funcional. CONCLUSÃO: o método descrito apresenta reprodutibilidade para utilização em pesquisas, assim como para a avaliação clínica das repercussões periodontais da movimentação dentária, ao permitir a comparação de imagens pré e pós-tratamento.INTRODUCTION: The thickness of the buccal and lingual bone plates constitutes one of the limiting factors of the orthodontic movement. The imaging technology has permitted the evaluation of this anatomical region, by means of cone beam computed tomography. PURPOSE: To describe and standardize, in details, a method for measuring the buccal and lingual bone plate thickness in CBCT images. METHODOLOGY: Digital standardization of face image should constitute the first step before the selection of CBCT slices. Two axial sections of each jaw were used for measuring the thickness

  4. Disgenesia do corpo caloso e más-formações associadas: achados de tomografia computadorizada e ressonância magnética Dysgenesis of the corpus callosum and associated malformations: computed tomography and magnetic resonance imaging findings

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    Cristiano Montandon

    2003-10-01

    Full Text Available O termo disgenesia do corpo caloso refere-se a uma má-formação deste com origem na embriogênese do telencéfalo. O relato analisa os achados de tomografia computadorizada e ressonância magnética em 11 pacientes com disgenesia calosa e em um caso de corpo caloso normal com lipoma associado. Esta pode ser distinguida em três grupos: agenesia total (três casos, agenesia parcial (seis casos e hipoplasia (dois casos. Anomalias associadas foram observadas em nove casos, incluindo má-formação de Chiari tipo II (um caso, esquizencefalia (um caso, cisto inter-hemisférico (dois casos, heterotopia nodular (um caso, cisto de Dandy-Walker (um caso e lipoma do corpo caloso (quatro casos. Este artigo demonstra um espectro destes distúrbios, auxiliando na sua interpretação diagnóstica.Callosal dysgenesis is a malformation of the corpus callosum with origins in the embryogenesis of the telencephalon. We reviewed the computed tomography and magnetic resonance imaging findings of 11 patients with callosal dysgenesis and one patient with normal corpus callosum associated with a lipoma. The patients were divided into three distinct groups: total agenesis (three patients, partial agenesis (six patients and hypoplasia (two patients. Associated abnormalities were observed in nine patients, including Chiari II malformation (one patient, schizencephaly (one patient, interhemispheric cyst (two patients, Dandy-Walker cyst (one patient, nodular heterotopy (one patient and lipoma of the corpus callosum (four patients. This paper presents a review that may contribute to the diagnosis of these disorders.

  5. Osteoporosis and prevention. Assessment of mineral density, geometry and biomechanics of bone by means of peripheral quantitative Computed Tomography (pQCT) in premenopausal women assuming phytoestrogens; Osteoporosi e fitoestrogeni: valutazione della densita' minerale ossea mediante tomografia computerizzata quantitativa periferica nelle donne lattoovovegetariane nella premenopausa

    Energy Technology Data Exchange (ETDEWEB)

    Di Leo, C; Tarolo, G L; Bestetti, A; Tagliabue, L; Del Sole, A; Alberti, G [Ospedale San Paolo, Milan (Italy). Servizio di Medicina Nucleare; Cestaro, B [Milan Univ., Milan (Italy). Cattedra e Scuola di Specializzazione in Medicina Nucleare; Pepe, L [ACN-L' Accessorio Nucleare, Cerro Maggiore, MI (Italy). Lab. Nucleari

    2000-04-01

    Aim of the work was to describe the noninvasive assessment of bone mineral density, geometrical and biochemical properties in premenopausal women with dietary intake of phytoestrogens and comparison of these parameters with those of age-matched female subjects with Mediterranean dietary intake lacking in these substances. Volumetric cortical, trabecular and total mineral density and bone geometrical properties were evaluated with peripheral quantitative computed tomography (pQCT) at the distal radius of the non dominant forearm. pQCT showed higher bone mineral density (total and trabecular) and SSI values in premenopausal with dietary intake of phytoestrogens. Despite the lack of statistical significance, these preliminary results, should further support the few literature findings about the potential role of phytoestrogens consumption in preventing trabecular bone loss. However, further studies are warranted to evaluate definitively postmenopausal osteoporosis. [Italian] Scopo del lavoro e' quello di studiare in modo non-invasivo la densita' minerale, le caratteristiche geometriche e biomeccaniche dell'osso in donne lattoovovegetariane nella premenopausa che assumevano con la dieta fitoestrogeni e confrontare questi dati con quelli di donne anch'esse in premenopausa, con dieta di tipo mediterraneo assolutamente priva di questi elementi con azione simil-ormonale. La densita' minerale, le proprieta' geometriche meccaniche dell'osso sono state valutate a livello del radio ultradistale non dominante mediante tomografia computerizzata (TC) quantitativa periferica, che nelle donne in premenopausa con dieta ricca di fitoestrogeni ha evidenziato valori della densita' minerale ossea totale, trabecolare e di resistenza ossea piu' elevati, anche se in modo non significativo, rispetto a quelli dei controlli con dieta mediterranea. Questi risultati preliminari suggerirebbero come l'assunzione quotidiana di fitoestrogeni attraverso la soia potrebbe accompagnarsi a un maggiore

  6. Osteoporosis and prevention. Assessment of mineral density, geometry and biomechanics of bone by means of peripheral quantitative Computed Tomography (pQCT) in premenopausal women assuming phytoestrogens; Osteoporosi e fitoestrogeni: valutazione della densita' minerale ossea mediante tomografia computerizzata quantitativa periferica nelle donne lattoovovegetariane nella premenopausa

    Energy Technology Data Exchange (ETDEWEB)

    Di Leo, C.; Tarolo, G.L.; Bestetti, A.; Tagliabue, L.; Del Sole, A.; Alberti, G. [Ospedale San Paolo, Milan (Italy). Servizio di Medicina Nucleare; Cestaro, B. [Milan Univ., Milan (Italy). Cattedra e Scuola di Specializzazione in Medicina Nucleare; Pepe, L. [ACN-L' Accessorio Nucleare, Cerro Maggiore, MI (Italy). Lab. Nucleari

    2000-04-01

    Aim of the work was to describe the noninvasive assessment of bone mineral density, geometrical and biochemical properties in premenopausal women with dietary intake of phytoestrogens and comparison of these parameters with those of age-matched female subjects with Mediterranean dietary intake lacking in these substances. Volumetric cortical, trabecular and total mineral density and bone geometrical properties were evaluated with peripheral quantitative computed tomography (pQCT) at the distal radius of the non dominant forearm. pQCT showed higher bone mineral density (total and trabecular) and SSI values in premenopausal with dietary intake of phytoestrogens. Despite the lack of statistical significance, these preliminary results, should further support the few literature findings about the potential role of phytoestrogens consumption in preventing trabecular bone loss. However, further studies are warranted to evaluate definitively postmenopausal osteoporosis. [Italian] Scopo del lavoro e' quello di studiare in modo non-invasivo la densita' minerale, le caratteristiche geometriche e biomeccaniche dell'osso in donne lattoovovegetariane nella premenopausa che assumevano con la dieta fitoestrogeni e confrontare questi dati con quelli di donne anch'esse in premenopausa, con dieta di tipo mediterraneo assolutamente priva di questi elementi con azione simil-ormonale. La densita' minerale, le proprieta' geometriche meccaniche dell'osso sono state valutate a livello del radio ultradistale non dominante mediante tomografia computerizzata (TC) quantitativa periferica, che nelle donne in premenopausa con dieta ricca di fitoestrogeni ha evidenziato valori della densita' minerale ossea totale, trabecolare e di resistenza ossea piu' elevati, anche se in modo non significativo, rispetto a quelli dei controlli con dieta mediterranea. Questi risultati preliminari suggerirebbero come l'assunzione quotidiana di fitoestrogeni

  7. Central nervous system abnormalities on midline facial defects with hypertelorism detected by magnetic resonance image and computed tomography Anomalias de sistema nervoso central em defeitos de linha média facial com hipertelorismo detectados por ressonância magnética e tomografia computadorizada

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    Vera Lúcia Gil-da-Silva-Lopes

    2006-12-01

    Full Text Available The aim of this study were to describe and to compare structural central nervous system (CNS anomalies detected by magnetic resonance image (MRI and computed tomography (CT in individuals affected by midline facial defects with hypertelorism (MFDH isolated or associated with multiple congenital anomalies (MCA. The investigation protocol included dysmorphological examination, skull and facial X-rays, brain CT and/or MRI. We studied 24 individuals, 12 of them had an isolated form (Group I and the others, MCA with unknown etiology (Group II. There was no significative difference between Group I and II and the results are presented in set. In addition to the several CNS anomalies previously described, MRI (n=18 was useful for detection of neuronal migration errors. These data suggested that structural CNS anomalies and MFDH seem to have an intrinsic embryological relationship, which should be taken in account during the clinical follow-up.Este estudo objetivou descrever e comparar as anomalias estruturais do sistema nervoso central (SNC detectadas por meio de ressonância magnética (RM e tomografia computadorizada (TC de crânio em indivíduos com defeitos de linha média facial com hipertelorismo (DLMFH isolados ou associados a anomalias congênitas múltiplas (ACM. O protocolo de investigação incluiu exame dismorfológico, RX de crânio e face, CT e RM de crânio. Foram estudados 24 indivíduos, sendo que 12 apresentavam a forma isolada (Grupo I e os demais, DLMFH com ACM de etiologia não esclarecida (Grupo II. Não houve diferença entre os dois grupos e os resultados foram agrupados. Além de várias anomalias de SNC já descritas, a RM foi útil para detecção de erros de migração neuronal. Os dados sugerem que as alterações estruturais de SNC e os DLMFH têm relação embriológica, o que deve ser levado em conta durante o seguimento clínico.

  8. Heat transfer and critical heat flux in a asymmetrically heated tube helicoidal flow; Transfert thermique et flux critique dans un ecoulement helicoidal en tube chauffe asymetriquement

    Energy Technology Data Exchange (ETDEWEB)

    Boscary, J

    1995-10-01

    The design of plasma facing components is crucial for plasma performance in next fusion reactors. These elements will be submitted to very high heat flux. They will be actively water-cooled by swirl tubes in the subcooled boiling regime. High heat flux experiments were conducted in order to analyse the heat transfer and to evaluate the critical heat flux. Water-cooled mock-ups were one-side heated by an electron beam gun for different thermal-hydraulic conditions. The critical heat flux was detected by an original method based on the isotherm modification on the heated surface. The wall heat transfer law including forced convection and subcooled boiling regimes was established. Numerical calculations of the material heat transfer conduction allowed the non-homogeneous distribution of the wall temperature and of the wall heat flux to be evaluated. The critical heat flux value was defined as the wall maximum heat flux. A critical heat flux model based on the liquid sublayer dryout under a vapor blanket was established. A good agreement with test results was found. (author). 198 refs., 126 figs., 21 tabs.

  9. Auxílio da tomografia computadorizada no planejamento pré-operatório de pacientes portadores de escoliose idiopática do adolescente Auxilio de la tomografía computarizada en el plan preoperatorio de pacientes portadores de escoliosis idiopática del adolescente Computed tomography aid in preoperative planning of patients with adolescent idiopathic scoliosis

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    Rodrigo Rezende

    2010-03-01

    Full Text Available A escoliose idiopática do adolescente (EIA é uma doença diagnosticada no início da puberdade. Ela apresenta etiologia indefinida e caracteriza-se pelo desvio lateral da coluna vertebral maior que 10°, associado à rotação do corpo vertebral. O uso de instrumentação de terceira geração produziu um melhor resultado na correção da curva do que as técnicas anteriores. Porém, ainda existem dificuldades técnicas no momento da passagem e da escolha dos parafusos pediculares, devido à angulação e ao diâmetro dos pedículos vertebrais. Apesar de apresentar vantagens, essa técnica não é isenta de riscos e complicações, necessitando de uma maior curva de aprendizado pelo médico-cirurgião, bem como de um adequado planejamento pré-operatório. Até o momento, não há na literatura relato sobre a utilização da tomografia computadorizada no auxílio do planejamento cirúrgico de pacientes com escoliose. Diante do exposto, objetivamos, no presente estudo, descrever uma técnica de planejamento pré-operatório, com o auxílio da tomografia computadorizada para a fixação da coluna em pacientes com escoliose idiopática do adolescente, especificando a angulação e o diâmetro dos pedículos vertebrais, o que poderá auxiliar o médico-cirurgião no momento da fixação.La escoliosis idiopática en el adolescente (EIA es una enfermedad diagnosticada en el inicio de la pubertad. Esta presenta una etiología indefinida y es caracterizada por el desvío lateral de la columna vertebral por encima de los diez grados asociados a la rotación del cuerpo vertebral. El uso de instrumentación de tercera generación produjo un mejor resultado en la corrección de la curva comparado con las técnicas anteriores. Sin embargo, existen dificultades técnicas en el momento del paso y de escoger los tornillos pediculares debido a la angulación y al diámetro de los pedículos vertebrales. A pesar de presentar ventajas, esta técnica no est

  10. Avaliando a difusão de tecnologias médicas no sistema de saúde privado no Brasil: o caso da tomografia por emissão de pósitrons (PET Assessing the use of medical technology in the private health system in Brazil: the case of Positron Emission Tomography (PET

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    Ana Luiza d´Ávila Viana

    2010-11-01

    Full Text Available OBJETIVOS: analisar os determinantes da difusão da tomografia por emissão de pósitrons (PET em um conjunto selecionado de prestadores de serviços e operadoras de planos de saúde no Brasil. MÉTODOS: estudo de caso qualitativo, com coleta de dados realizada por meio de entrevistas em profundidade (N=9 com representantes de quatro prestadores de serviços de saúde privados e três operadoras de planos de saúde. RESULTADOS: as decisões para aquisição da tecnologia estudada são tomadas por dirigentes de hospitais e clínicas que adotam uma estratégia de diferenciação baseada em liderança tecnológica. Os fatores que influenciam essa decisão são: histórico de pioneirismo da instituição na incorporação de tecnologias; pressão do corpo clínico vinculado à instituição; prestígio do médico ou da área demandante; disponibilidade de recursos financeiros; acesso facilitado à tecnologia; concorrência entre os prestadores de serviços de saúde; evidências científicas; e rentabilidade do investimento. CONCLUSÕES: os atuais instrumentos de política usados para gerenciar a difusão de tecnologias médicas no sistema de saúde brasileiro exercem pouca influência nas decisões de grandes prestadores privados, cujas atividades não estão necessariamente relacionadas com as necessidades de saúde da população ou com as prioridades da política de saúde.OBJECTIVES: to analyze the determining factors underlying the extent to which positron emission tomography (PET is used in a selected medical services provider covered by private health insurance plans in Brazil. METHODS: a qualitative case study was undertaken with data collected by means of in-depth interviews (N=9 with representatives of four private health service providers and three health insurance plan operators. RESULTS: the decisions to acquire the technology under study are taken by managers of hospitals and clinics that adopt a strategy based on excellence in

  11. Reprodutibilidade das mensurações da espessura das tábuas ósseas na tomografia computadorizada Cone-Beam utilizando diferentes protocolos de aquisição de imagem Reproducibility of bone plate thickness measurements with Cone-Beam Computed Tomography using different image acquisition protocols

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    Carolina Carmo de Menezes

    2010-10-01

    Full Text Available INTRODUÇÃO: quanto menor a dimensão do voxel, maior a nitidez da imagem de tomografia computadorizada Cone-Beam (TCCB, porém, maior a dose de radiação emitida. OBJETIVOS: avaliar e comparar a reprodutibilidade da mensuração da espessura das tábuas ósseas vestibular e lingual em imagens de TCCB, utilizando diferentes protocolos de aquisição de imagem com variação da dimensão do voxel. MÉTODOS: exames de TCCB foram tomados de 12 mandíbulas humanas secas, com dimensão do voxel de 0,2; 0,3 e 0,4mm, no aparelho i-CAT Cone-Beam 3-D Dental Imaging System. No software i-CAT Viewer, foi mensurada a espessura das tábuas ósseas vestibular e lingual, em um corte axial passando 12mm acima do forame mentoniano do lado direito. A reprodutibilidade intraexaminador foi avaliada por meio da aplicação do teste t pareado. Para a comparação interexaminadores, foi utilizado o teste t independente. Os resultados foram considerados com o nível de significância de 5%. RESULTADOS: observou-se uma excelente reprodutibilidade interexaminadores para os três protocolos avaliados. A reprodutibilidade intraexaminadores foi muito boa, com exceção de algumas regiões dos dentes anteriores, que mostraram diferenças estatisticamente significativas, independentemente da dimensão do voxel. CONCLUSÃO: a mensuração da espessura das tábuas ósseas vestibular e lingual em imagens de TCCB mostrou boa precisão para exames obtidos com voxel de 0,2; 0,3 ou 0,4mm. A reprodutibilidade das mensurações na região anterior da mandíbula foi mais crítica do que na região posterior.INTRODUCTION: A smaller voxel dimension leads to greater resolution of Cone-Beam Computed Tomography (CBCT, but a greater dosage of radiation is emitted. OBJECTIVE: Assess and compare the reproducibility of buccal and lingual bone plate thickness measurements in CBCT images using different image acquisition protocols, with variations in the voxel dimension. METHODS: CBCT exams

  12. Estudo de caso de oferta induzindo a demanda: o caso da oferta de exames de imagem (tomografia axial computadorizada e ressonância magnética na Unimed-Manaus Case study of supply induced demand: the case of provision of imaging scans (computed tomography and magnetic resonance at Unimed-Manaus

    Directory of Open Access Journals (Sweden)

    Edson de Oliveira Andrade

    2011-04-01

    Full Text Available OBJETIVO: Apresentar a experiência de uma operadora de plano de saúde (Unimed-Manaus na cidade de Manaus, Estado do Amazonas, com o credenciamento de serviços de imagem e a indução de demanda pela oferta dos novos serviços (Lei de Roemer. MÉTODOS: Trata-se de uma pesquisa de caráter retrospectivo, com estudo de série temporal, abordando o período de janeiro de 1998 a junho de 2004, lapso de tempo em que ocorreu a implantação dos serviços de tomografia computadorizada e da ressonância magnética no âmbito dos serviços oferecidos por aquele plano de saúde. A análise estatística consistiu em uma parte descritiva e uma inferencial, sendo esta última utilizando teste paramétrico de média (teste t de Student e ANOVA e o teste de correlação de Pearson. Foi adotado um alfa de 5% e um intervalo de confiança de 95%. RESULTADOS: Foi possível identificar na Unimed-Manaus que a oferta de novos serviços de imagem foi capaz de, por si só, gerar um aumento da demanda do serviço caracterizando o fenômeno descrito por Roemer. CONCLUSÃO: Os resultados deste trabalho ressaltam a necessidade de se estar atento ao fato de que a oferta de novos serviços no setor da saúde poderá acarretar, por si só, um aumento de sua utilização sem que haja uma demanda real.OBJECTIVE: To present the experience of a health plan operator (Unimed-Manaus in Manaus, Amazonas, Brazil, with the accreditation of imaging services and the demand induced by the supply of new services (Roemer's Law. METHODS: This is a retrospective work studying a time series covering the period from January 1998 to June 2004, in which the computed tomography and the magnetic resonance imaging services were implemented as part of the services offered by that health plan operator. Statistical analysis consisted of a descriptive and an inferential part, with the latter using a mean parametric test (Student T-test and ANOVA and the Pearson correlation test. A 5% alpha and a 95

  13. Emprego das medidas anatômicas do buraco macular idiopático obtidas pela tomografia de coerência óptica como fator preditivo nos resultados visuais: um estudo piloto Use of anatomical measures of idiopathic macular hole obtained through optical coherence tomography as a predictive factor in visual results: a pilot study

    Directory of Open Access Journals (Sweden)

    Alan Diego Negretto

    2007-10-01

    Full Text Available OBJETIVO: Avaliar a anatomia do buraco macular idiopático (BMI a partir da tomografia de coerência óptica (OCT e construir índice prognóstico que possa ser correlacionado com os resultados visuais e o fechamento anatômico. MÉTODOS: Estudo prospectivo, no qual 22 olhos com BMI foram avaliados pelo OCT no pré-operatório da cirurgia do BMI. Foi criado o índice prognóstico do buraco macular (IPBM que foi correlacionado com o resultado anatômico e a acuidade visual pós-operatória seis meses após a cirurgia. RESULTADOS: Dezesseis olhos (72,7% obtiveram fechamento anatômico ao final de seis meses de acompanhamento. Na análise do IPBM, houve diferença significativa entre o grupo 1 (BM aberto e o grupo 2 (BM fechado (p=0,0018. O risco de insucesso para o fechamento anatômico é 11 vezes maior quando o diâmetro da base interna for superior a 600 µm ou o IPBM for inferior a 0,6 (p=0,0495. No que diz respeito à AV final, observou-se que o IPBM tem correlação negativa significante na AV (p=0,001. CONCLUSÃO: O IPBM se apresentou como o melhor preditor de fechamento anatômico e acuidade visual pós-operatória entre as variáveis aqui estudadas. Responde por 41% da acuidade visual pós-operatória final, nos levando a crer que outros fatores, como o tempo de história e a degeneração dos fotorreceptores nestes BM mais antigos, possam estar envolvidos nos resultados visuais.PURPOSE: To evaluate the anatomy of idiopathic macular hole (IMH using Optical Coherence Tomography (OCT and to construct a prognostic index that can be correlated with the visual outcomes and the anatomical closing. METHODS: Prospective study, in which 22 eyes with IMH had been evaluated through OCT in the daily postoperative period of IMH surgery. The Prognostic of Macular Hole Index (PMHI was created which was correlated with the anatomical result and the postoperative visual acuity (VA six months after surgery. RESULTS: Sixteen eyes (72.7% got anatomical

  14. Opacidades em vidro fosco nas doenças pulmonares difusas: correlação da tomografia computadorizada de alta resolução com a anatomopatologia Ground-glass opacity in diffuse lung diseases: high-resolution computed tomography-pathology correlation

    Directory of Open Access Journals (Sweden)

    Maria Lúcia de Oliveira Santos

    2003-12-01

    Full Text Available Opacidade em vidro fosco é achado freqüentemente visto na tomografia computadorizada de alta resolução do tórax e se traduz pelo aumento do coeficiente de atenuação dos pulmões, mas sem apagar as marcas broncovasculares. Por sua inespecificidade, a associação com outros achados radiológicos, clínicos e anatomopatológicos deve ser considerada para uma interpretação diagnóstica mais correta. Neste trabalho foram analisados 62 exames tomográficos de pacientes com doenças pulmonares difusas, de 14 etiologias diferentes, em que opacidades em vidro fosco foram o achado único ou predominante, e feita correlação anatomopatológica por meio de biópsias ou necropsias. Na pneumocistose as opacidades em vidro fosco corresponderam, histologicamente, à ocupação alveolar por material espumoso contendo parasitos; no carcinoma bronquíolo-alveolar, a espessamento dos septos alveolares e ocupação de sua luz por muco e células tumorais; na paracoccidioidomicose, a espessamento dos septos alveolares, áreas de fibrose e alvéolos contendo exsudato broncopneumônico; na sarcoidose, a fibrose ou a acúmulo de granulomas; na fibrose pulmonar idiopática, a espessamento dos septos alveolares por fibrose; na bronquiolite obliterante com pneumonia em organização, a pneumonia intersticial com áreas de organização intra-alveolar. A ocupação alveolar por sangue foi observada nos casos de leptospirose, hemossiderose idiopática, metástases de tumor renal e na aspergilose invasiva; por vacúolos de gordura na pneumonia lipídica; por material protéico e lipoprotéico na silicoproteinose e na proteinose alveolar; e por líquido de edema na insuficiência cardíaca congestiva.Ground-glass opacity is a finding frequently seen in high-resolution computed tomography examinations of the chest and is characterized by hazy increased attenuation of lung, however without blurring of bronchial and vascular margins. Due to its unspecificity

  15. Tomografia computadorizada de alta resolução na silicose: correlação com radiografia e testes de função pulmonar High-resolution computed tomography in silicosis: correlation with chest radiography and pulmonary function tests

    Directory of Open Access Journals (Sweden)

    Agnaldo José Lopes

    2008-05-01

    Full Text Available OBJETIVO: Correlacionar os parâmetros tomográficos com os de função pulmonar em portadores de silicose, bem como comparar os resultados da tomografia computadorizada de alta resolução (TCAR com os da radiografia de tórax. MÉTODOS: Foi realizado um estudo de corte transversal, em que foram avaliados 44 pacientes não-tabagistas e sem história pregressa de tuberculose. As radiografias foram classificadas de acordo com a proposta da Organização Internacional do Trabalho. Utilizando um sistema de escore semiquantitativo, os seguintes achados na TCAR foram quantificados: extensão total do envolvimento pulmonar, opacidades parenquimatosas e enfisema. Foram realizados espirometria, oscilações forçadas, avaliação dos volumes pulmonares pela técnica de diluição com hélio e medida da diffusing capacity of the lung for carbon monoxide (DLCO, capacidade de difusão do monóxido de carbono. RESULTADOS: Dos 44 pacientes estudados, 41 eram homens, com média de idade de 48,4 anos. Na análise comparativa, 4 pacientes classificados na categoria 0 pela radiografia foram reclassificados na categoria 1 pela TCAR e, enquanto a radiografia diagnosticou 23 casos de fibrose maciça progressiva, a TCAR estabeleceu esse diagnóstico em 33 doentes. Para o escore de opacidades, as maiores correlações foram observadas com as medidas de fluxo, DLCO e complacência. Já o enfisema correlacionou-se negativamente com as medidas de volume, DLCO e fluxo. Nesta amostra com predomínio de grandes opacidades (75% dos indivíduos, a deterioração da função pulmonar associou-se com a extensão das alterações estruturais. CONCLUSÕES: Na silicose, a TCAR é superior à radiografia tanto na detecção precoce da doença quanto na identificação de fibrose maciça progressiva.OBJECTIVE: To correlate tomographic findings with pulmonary function findings, as well as to compare chest X-ray findings with high resolution computed tomography (HRCT findings, in

  16. Heat transfer performance during condensation of R-134a inside helicoidal tubes

    International Nuclear Information System (INIS)

    Al-Hajeri, M.H.; Koluib, A.M.; Mosaad, M.; Al-Kulaib, S.

    2007-01-01

    This paper reports an experimental investigation of condensation heat transfer and pressure drop of an ozone friendly refrigerant, R-134a, inside a helical tube for climatic conditioning of hot regions. This study concerns the condensation of R-134a flowing through annular helical tubes with different operating refrigerant saturated temperatures. The average pressure drop is measured and compared with data from relevant literature. The measurements of R-134a were performed on mass flow flux ranges from 50 to 680 kg/m 2 s. The study provides experimental data that could be used for the design and development of more efficient condensers for refrigeration and air conditioning (A/C) systems working with the same refrigerant

  17. In vivo thermoluminescent dosimetry in studies of helicoid computed tomography and excretory urogram

    International Nuclear Information System (INIS)

    Cruz C, D.; Azorin N, J.; Saucedo A, V.M.; Barajas O, J.L.

    2005-01-01

    The dosimetry is the field of measurement of the ionizing radiations. It final objective is to determine the 'absorbed dose' for people. The dosimetry is vital in the radiotherapy, the radiological protection and the treatment technologies by irradiation. Presently work, we develop 'In vivo' dosimetry, in exposed patients to studies of helical computed tomography and excretory urogram. The dosimetry 'in vivo' was carried out in 20 patients selected aleatorily, for each medical study. The absorbed dose was measured in points of interest located in crystalline, thyroid, chest and abdomen of each patient, by means of thermoluminescent dosemeters (TLD) LiF: Mg,Cu,P + Ptfe of national fabrication. Also it was quantified the dose in the working area. (Author)

  18. Design Optimization and Characterization of Helicoidal Composites with Enhanced Impact Resistance

    Science.gov (United States)

    2011-01-12

    The sim are not shea n in the last the fiber di fined to a sp eft : 0/90; right chanisms in e able to qu utes the im e able to a in the helic ated...held in place with several pieces of wadding that was gently tapped down. With the wadding in position the FSP     is placed Once the A remote screen

  19. Analysis of the transformations temperatures of helicoidal Ti-Ni actuators using computational numerical methods

    Directory of Open Access Journals (Sweden)

    Carlos Augusto do N. Oliveira

    2013-01-01

    Full Text Available The development of shape memory actuators has enabled noteworthy applications in the mechanical engineering, robotics, aerospace, and oil industries and in medicine. These applications have been targeted on miniaturization and taking full advantage of spaces. This article analyses a Ti-Ni shape memory actuator used as part of a flow control system. A Ti-Ni spring actuator is subjected to thermomechanical training and parameters such as transformation temperature, thermal hysteresis and shape memory effect performance were investigated. These parameters were important for understanding the behavior of the actuator related to martensitic phase transformation during the heating and cooling cycles which it undergoes when in service. The multiple regression methodology was used as a computational tool for analysing data in order to simulate and predict the results for stress and cycles where the experimental data was not developed. The results obtained using the training cycles enable actuators to be characterized and the numerical simulation to be validated.

  20. Heat transfer and critical heat flux in a asymmetrically heated tube helicoidal flow

    International Nuclear Information System (INIS)

    Boscary, J.

    1995-10-01

    The design of plasma facing components is crucial for plasma performance in next fusion reactors. These elements will be submitted to very high heat flux. They will be actively water-cooled by swirl tubes in the subcooled boiling regime. High heat flux experiments were conducted in order to analyse the heat transfer and to evaluate the critical heat flux. Water-cooled mock-ups were one-side heated by an electron beam gun for different thermal-hydraulic conditions. The critical heat flux was detected by an original method based on the isotherm modification on the heated surface. The wall heat transfer law including forced convection and subcooled boiling regimes was established. Numerical calculations of the material heat transfer conduction allowed the non-homogeneous distribution of the wall temperature and of the wall heat flux to be evaluated. The critical heat flux value was defined as the wall maximum heat flux. A critical heat flux model based on the liquid sublayer dryout under a vapor blanket was established. A good agreement with test results was found. (author). 198 refs., 126 figs., 21 tabs

  1. Helical CT defecography; La defecografia con Tomografia Computerizzata spirale

    Energy Technology Data Exchange (ETDEWEB)

    Ferrando, R.; Fiorini, G.; Beghello, A.; Cicio, G.R.; Derchi, L.E.; Consigliere, M.; Resasco, M. [Genua Univ., Genua (Italy). Ist. di Radiologia, Cattedra R; Tornago, S. [Genua Univ. Genua (Italy). 2 Clinica Ortopedica

    1999-11-01

    The purpose of this work is to investigate the possible role of Helical CT defecography in pelvic floor disorders by comparing the results of the investigations with those of conventional defecography. The series analyzed consisted of 90 patients, namely 62 women and 28 men, ranging in age 24-82 years. They were all submitted to conventional defecography, and 18 questionable cases were also studied with Helical CT defecography. The conventional examination was performed during the 4 standard phases of resting, squeezing, Valsalva and straining; it is used a remote-control unit. The parameters for Helical CT defecography were: 5 mm beam collimation, pitch 2, 120 KV, 250 m As and 18-20 degrees gantry inclination to acquire coronal images of the pelvic floor. The rectal ampulla was distended with a bolus of 300 mL nonionic iodinated contrast agent (dilution: 3g/cc). The patient wore a napkin and was seated on the table, except for those who could not hold the position and were thus examined supine. Twenty-second helical scans were performed at rest and during evacuation; multiplanar reconstructions were obtained especially on the sagittal plane for comparison with conventional defecographic images. Coronal Helical CT defecography images permitted to map the perineal floor muscles, while sagittal reconstructions provided information on the ampulla and the levator ani. To conclude, Helical CT defecography performed well in study of pelvic floor disorders and can follow conventional defecography especially in questionable cases. [Italian] Scopo di questo lavoro e' ricercare un ruolo per la defeco-TC con apparecchiatura elicoidale nello studio delle malattie del pavimento pelvico confrontandola con i risultati consolidati della defecografia tradizionale. Si sono visionati 90 pazienti, 62 femmine e 28 maschi, con eta' compresa tra 24 e 82 anni, con defecografia tradizionale; di questi, 18 casi con diagnosi dubbia sono stati studiati anche con defeco-TC spirale. Per la defecografia tradizionale si e' utilizzato un apparecchio telecomandato e valutato le quattro fasi di: riposo, trattenimento, ponzamento e spinta. Per lo studio con TC e' stata eseguita acquisizione volumetrica spirale con collimazione del fascio di 5 mm, pitch 2, 120 kV, 250 m As e inclinazione del tunnel di scansione di 18-20 gradi verso il paziente al fine di ottenere piani coronali del pavimento pelvico. Il paziente dotato di pannolone per adulti e' posizionato a cavalcioni del tavolo porta-paziente in posizione da motociclista, previa distensione dell'ampolla rettale con bolo fecale costituito da 300 ml di mdc iodato non ionico con la diluizione di 3 g di iodio per 100 ml. L'esame e' stato eseguito nella posizione supina nei casi nei quali i pazienti non riuscivano a mantenere la posizione. E' stata eseguita acquisizione volumetrica spirale di 20 secondi nella fase di riposo e di spinta con ricostruzioni multiplanari specie sul piano sagittale per il confronto con le immagini con la defecografia tradizionale. La defeco-TC ha consentito di evidenziare malattie estrinseche all'apparato ano-rettale, risultando esame di seconda istanza rispetto alla defecografia tradizionale ma dirimente nei casi dubbi per la possibilita' di valutare il trofismo dei muscoli deputati all'atto defecatorio e le strutture contigue attraverso le ricostruzioni multiplanari con alta risoluzione.

  2. 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

    Directory of Open Access Journals (Sweden)

    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

  3. Uso da tomografia de coerência ótica intracoronariana para caracterização precisa da aterosclerose Uso de la tomografía de coherencia óptica intracoronaria para caracterización precisa de la aterosclerosis Use of optical coherence tomography for accurate characterization of atherosclerosis

    Directory of Open Access Journals (Sweden)

    John Coletta

    2010-02-01

    Full Text Available A Tomografia de Coerência Ótica (TCO é uma nova tecnologia de imagem baseada em interferometria de baixa coerência que utiliza a dispersão de luz quase-infravermelha como uma fonte de sinal para fornecer imagens transversais vasculares com definição muito superior à de qualquer outra modalidade disponível. Com uma resolução espacial de até 10μm, a TCO fornece uma resolução 20 vezes maior do que o ultrassom intravascular (USIV, a modalidade atualmente mais utilizada para obter imagens intra-coronárias. A TCO tem uma capacidade de fornecer um entendimento das várias fases da doença aterosclerótica e a resposta vascular ao tratamento. Estudos tem mostrado a capacidade da TCO em detectar estruturas arteriais e ajudar na determinação de diferentes constituintes histológicos. Sua capacidade de distinguir diferentes graus de alterações ateroscleróticas e os vários tipos de placas, quando comparada à histologia, tem sido recentemente demonstrada com correlações inter e intra-observador aceitáveis para esses achados. A TCO fornece uma resolução endovascular excepcional em tempo real in vivo, que tem sido explorada para avaliar as estruturas vasculares e a resposta ao uso do equipamento. Embora a profundidade permaneça uma limitação para a caracterização de placa além de 2 mm através da TCO, uma resolução próxima à histológica pode ser obtida dentro do primeiro milímetro da parede do vaso, permitindo uma avaliação extraordinária das características e espessura da capa fibrosa. Além disso, a avaliação da cobertura de neoíntima, padrões de tecido para-haste e aposição de stent podem agora ser escrutinizados para hastes individuais na escala de mícrons, a assim chamada análise em nível de haste. A TCO levou a imagem intravascular ao nível de mícron na análise vascular in vivo e espera-se que breve se torne uma ferramenta valiosa e indispensável para cardiologistas em aplicações clínicas e de

  4. Aplicações da tomografia de ressonância magnética nuclear como método não-destrutivo para avaliar os efeitos de injúrias mecânicas em goiabas 'Paluma' e 'Pedro Sato' Applications of the nuclear magnetic resonance tomography as a non-destructive method to evaluate the effects of mechanical injuries in 'Paluma' and 'Pedro Sato' guavas

    Directory of Open Access Journals (Sweden)

    Ben-Hur Mattiuz

    2002-12-01

    Full Text Available Objetivou-se determinar o potencial do uso da tomografia de ressonância magnética, como método não-destrutivo, para avaliar os efeitos das injúrias mecânicas em goiabas. Foram utilizados frutos no estádio de maturação "de vez" das cultivares Paluma e Pedro Sato. Na injúria por impacto, os frutos foram deixados cair, em queda livre, de uma altura de 1,20 m, sofrendo dois impactos, em lados opostos de sua porção equatorial. Na injúria por compressão, os frutos foram submetidos a um peso de 29,4 N, por 15 minutos. Para a injúria por corte, foram efetuados dois cortes, no sentido longitudinal dos frutos, de exatamente 30 mm de comprimento por 2 mm de profundidade. Os frutos injuriados foram armazenados sob condições de ambiente (22 ± 2 °C e 40 %UR. Foram realizadas análises com tomógrafo de ressonância magnética Varian Inova de 2 Tesla. As imagens foram obtidas a partir da detecção dos prótons de hidrogênio (¹H. Para cada fruto, foram obtidos tomogramas simétricos a partir do centro do fruto. A tomografia de ressonância magnética nuclear mostrou-se uma ferramenta eficaz na detecção de injúrias internas de frutos. O estresse físico causado pelo impacto produziu um colapso interno nos lóculos desses frutos (internal bruising, levando à perda da integridade celular e a conseqüente liquefação dos tecidos placentários. A cultivar Pedro Sato mostrou uma suscetibilidade maior à injúria por impacto que a 'Paluma'. A injúria por compressão tornou-se mais evidente no pericarpo externo do fruto, de ambas as cultivares. A injúria por corte levou a lignificação dos tecidos no local injuriado e deformações superficiais devido à perda acentuada de matéria fresca no local da lesão, evidentes no sexto dia de avaliação.The present study reports on the potential of the use of the tomography of magnetic resonance, as a non-destructive method, to evaluate the effects of the mechanical injuries in guava fruits

  5. A Probe-Compensated Helicoidal NF-FF Transformation for Aperture Antennas Using a Prolate Spheroidal Expansion

    Directory of Open Access Journals (Sweden)

    Amedeo Capozzoli

    2012-01-01

    Full Text Available A new probe-compensated near-field-far-field (NF-FF transformation for aperture antennas in a cylindrical scanning geometry is presented. Such a technique takes the advantage of the NF data acquisition made according to a very efficient sampling strategy along a helix and exploits a proper aperture field expansion based on the use of the prolate spheroidal wave functions (PSWFs, accounting for the a priori information on shape and size of the antenna under test. The unknown aperture field expansion coefficients of the PSWFs are evaluated from the acquired voltage samples by an inversion process using a regularized version of the singular value decomposition method. Experimental results on connected and disconnected radiating aperture antennas, including sum and difference patterns, show the effectiveness of the approach and, in particular, how it enables a serious reduction of the measurement points without impairing the FF estimation accuracy.

  6. Investigation of the resonant helicoidal fields on the activation/inhibition of the MHD oscillations in the TBR-1

    International Nuclear Information System (INIS)

    Araujo, M.S.T. de.

    1991-01-01

    The effect of resonant helical fields (CHR) on the plasma confined by the TBR-1 tokamak was investigated. The external perturbations were created by a set of windings located around the vacuum vessel. The field helicity corresponding to the components m/n = 2/1, m/n = 3/1 and m/n = 4/1 could be chosen, from two existing panels beside the tokamak. The main diagnostic used was a set of 10 Mirnov magnetic coils. For this work, a computer program, called MHD-FOUR, was created to Fourier-analyse the detected MHD oscillations. Therefore, the time evolution of every component ranging from m = to m = 4 could be separately obtained. The Spectral Analysis done on some parts of the discharges showed that two or more modes were coupled, and this coupling could justify the disruptive instability that occurred afterwards, while rather intense helical currents (I hel ≅ 400 - 500 A) were applied. The major disruptions were frequently observed to be preceded by a dominant m = 2 mode while, for the minor disruptions, besides the m = 2, also the m 3 component was found to be equally dominant. The modes growth rates were calculated using experimental data taken just before the occurrence of a disruptive instability. The results confirmed the resistive nature of the perturbations. The rational magnetic surfaces positions and the half-width of the corresponding islands were also estimated. The Chirikov criterion showed that the minor disruptions were preceded by an ergodization of the external part of the plasma column while before the major disruption the ergodization also comprised the internal region. This total ergodization of the plasma column was, most probably, the main cause for the destruction of the confinement. (author)

  7. Proteinose alveolar pulmonar Aspectos na tomografia computadorizada de alta resolução** Trabalho realizado nos Departamentos ou Serviços de Radiologia da Universidade Federal Fluminense (UFF - RJ; Hospital Universitário Clementino Fraga Filho - RJ; Faculdade de Medicina de São José do Rio Preto (FAMERP -SP; Universidade de Campinas (UNICAMP - SP; Pavilhão Pereira Filho - RS, e Universidade Federal de Santa Catarina - SC.

    Directory of Open Access Journals (Sweden)

    Erick Malheiro Leôncio Martins

    2002-07-01

    Full Text Available RESUMO: A proteinose alveolar pulmonar é uma doença rara cuja etiologia ainda permanece desconhecida. É caracterizada pelo preenchimento alveolar por um material proteináceo que determina um quadro pulmonar restritivo com hipoxemia e várias alterações radiológicas. Neste trabalho são analisadas e discutidas as alterações encontradas nas tomografias computadorizadas de alta resolução de doze pacientes com proteinose alveolar pulmonar. Seis casos eram da forma primária da doença, e os outros seis da secundária, estando associados à silicose, asbestose, leucemia, síndrome da imunodeficiência adquirida e lúpus eritematoso sistémico. O objectivo básico foi estudar as alterações tomográficas mais frequentes. Na maioria dos casos, os aspectos tomográficos foram correlacionados com os dados anatomopatológicos, provenientes de biópsias cirúrgicas ou necropsia. Os aspectos tomográficos mais frequentes foram as opacidades em vidro fosco, com distribuição geográfica, associadas a espessamento liso dos septos interlobulares, resultando no padrão de pavimentação em mosaico. Estas alterações foram encontradas em todos os pacientes com a forma primária, não predominando em nenhuma região pulmonar específica. Na forma secundária, cinco dos seis casos apresentavam alterações tomográficas não observadas na forma primária da doença como, por exemplo, placas pleurais, derrame pleural, nódulos centrolobulares, linfonodomegalias e padrão de vidro fosco sem associação com espessamento de septos interlobulares. Além disto, em três destes casos houve um predomínio das lesões nas regiões póstero-inferiores dos pulmões.REV PORT PNEUMOL 2002; VIII(4: 303-314 ABSTRACT: Pulmonary alveolar proteinosis is a rare condition and it’s etiology remains unknown. It is characterized by the accumulation

  8. Osteoporose vs. doença de Alzheimer e Parkinson usando a tomografia computorizada quantitativa

    OpenAIRE

    Rodrigues, José Artur Oliveira

    2013-01-01

    Dissertação de mestrado integrado em Engenharia Biomédica A osteoporose é reconhecida como um dos maiores problemas de saúde pública devido à elevada taxa de morbilidade e mortalidade e aos custos associados com a descalcificação dos ossos, originando fraturas ósseas. É uma doença caracterizada por uma densidade mineral óssea diminuída e por uma microdeterioração do tecido ósseo que conduzem a um aumento da fragilidade óssea e a um consequente aumento do risco de fraturas. A...

  9. Analysis of fetal dose in CT procedures; Analisis de dosis fetal en procedimientos de tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz Torres, A.; Plazas, M. C.

    2006-07-01

    It is the miracle of the life, that sublime formation, the given more beautiful gift for heaven's sake to our to exist, and it is consequently our responsibility to look after their protection and care. Today in day the quantity of radiation absorbed by the fetus in the treatments for radiodiagnostic, mainly in the procedures of on-line axial tomography, the fetus absorbs a considerable dose of radiation and the questions generated regarding if these doses, bear to a risk of malformations or if it is necessary the interruption of the pregnancy is very frequent. In most of the cases, the treatment with ionizing radiations that it is beneficial for the mother, is only indirectly it for the fetus that is exposed to a risk. The possibility that a fetus or a small boy contract cancer caused by the radiation it can be three times superior to that of the population in general, of there the importance of analyzing the goods of the prenatal irradiation and the main agents to consider for the estimate of the magnitude of the risk of the exhibitions in uterus. In the different circumstances in that these can happen in treatments of on-line axial tomography computerized. (Author)

  10. Analysis of the computed tomography in the acute abdomen; Analise da tomografia computadorizada no abdome agudo

    Energy Technology Data Exchange (ETDEWEB)

    Hochhegger, Bruno [Complexo Hospitalar Santa Casa de Porto Alegre, RS (Brazil); Moraes, Everton [Universidade Federal de Santa Maria (UFSM), RS (Brazil); Haygert, Carlos Jesus Pereira; Antunes, Paulo Sergio Pase [Hospital Universitario de Santa Maria, RS (Brazil); Gazzoni, Fernando [Pontificia Universidade Catolica de Porto Alegre (PUC-RS), Porto Alegre, RS (Brazil). Hospital Sao Lucas; Andrade, Rubens Gabriel Feijo [Fundacao Universitaria de Cardiologia de Porto Alegre, RS (Brazil). Inst. de Cardiologia; Bueno, Leticia Rossi [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil); Lopes, Luis Felipe Dias [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Dept. de Estatistica]. E-mail: brunorgs@pop.com.br

    2007-07-01

    Introduction: This study tends to test the capacity of the computed tomography in assist in the diagnosis and the approach of the acute abdomen. Material and method: This is a longitudinal and prospective study, in which were analyzed the patients with the diagnosis of acute abdomen. There were obtained 105 cases of acute abdomen and after the application of the exclusions criteria were included 28 patients in the study. Results: Computed tomography changed the diagnostic hypothesis of the physicians in 50% of the cases (p < 0.05), and the confidence index in 85.71% of the cases (p 0.014). Computed tomography also altered the management in 46.43% of the cases (p > 0.05), where 78.57% of the patients had surgical indication before computed tomography and 67.86% after computed tomography (p = 0.0546). The index of accurate diagnosis of computed tomography, when compared to the anatomopathologic examination and the final diagnosis, was observed in 82.14% of the cases (p = 0.013). When the analysis was done dividing the patients in surgical and nonsurgical group, were obtained an accuracy of 89.28% (p 0.0001). The difference of 7.2 days of hospitalization (p = 0.003) was obtained compared with the mean of the acute abdomen without use the computed tomography. Conclusion: The computed tomography is correlative with the anatomopathology and has great accuracy in the surgical indication, associated with the capacity of increase the confident index of the physicians, reduces the hospitalization time, reduces the number of surgeries and is cost-effective. (author)

  11. Le leucodistrofie: aspetti clinici e quadri con Tomografia Computerizzata e con Risonanza Magnetica

    International Nuclear Information System (INIS)

    Magnaldi, S.

    1991-01-01

    Leukodystrophies are inherited white matter diseases due to abnormalities occurring in myelin synthesis and/or maintenance. The most common types of these rare childhood conditions are represented by adrenoleukodystrophy, metachromatic leukodystrophy, Canavan's, Alexander's, Krabbe's, and Pelizaeus-Merzbacher's diseases. Most of them are lethal during childhood, with the exception of the adrenoleukodystrophy-adrenomyeloneuropathy complex, which sometimes, during its early phases, may be cured with a dietary therapy. The aims of this paper are: 1) the description of inheritance factors, pathogenesis, pathological and clinical findings of each of the most frequent childhood leukodystrophies; 2) the description of the most common patterns of these conditions on CT and MR imaging; 3) the evaluation of the diagnostic capabilities of these two imaging techniques and the comparison of their results. Finally, some of the therapies suggested for the mild forms of these conditions are discussed. The evaluation of leukodystrophic patients with CT and MR imaging shows both imaging modalities to have high sensitivity, thanks to the detection of abnormally myelinated areas, which appear hypodense on CT and Hypertense on T2-weighted MR images. Frequently, both imaging modalities exhibit high specificity as well: they allow a differential diagnosis between the different types through the demonstration of their location in the early stages and of their mode of spread. The most typical example is represented by adrenoleukodystrophy, which is the most common type of leukodystrophy: the frequent occipito-parietal onset and the anterior and caudal progression allow a correct diagnosis to be made on CT and MR images in most cases. The comparison between CT and MR findings demonstrates a slight superiority of the latter: multiplanarity and high contrast resolution make MR imaging more sensitive than CT in the detection of the both caudal spread and involvement of optic and acoustic nervous pathways. Furthermore, MR imaging allows a safe follow-up in children with leukodystrophy

  12. Coronary CT: clinical indications and future directions; Tomografia de coronarias: indicacoes clinicas e perspectivas futuras

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, Cesar H.; Serpa, Bruna S.; Kay, Fernando U.; Szarf, Gilberto; Passos, Rodrigo B.; Neto, Roberto S.; Chate, Rodigo C.; Funar, Marcelo B., E-mail: cesarnomura@gmail.com [Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Cury, Roberto C. [Hospital Samaritano, Sao Paulo, SP (Brazil)

    2011-01-15

    Multidetector computed tomography (MDCT) has started its implementation in cardiology with calcium quantification of coronary plaques in the study without contrast, using the calcium score, demonstrating an important independent predictor of future cardiac events. The examination with intravenous contrast, coronary angiography, appeared later as a noninvasive method for evaluation of anatomy and obstructive coronary disease, characterizing the degree of stenosis and the presence of non calcified atherosclerotic plaques, assessing not only the lumen, but also the vessel wall. With the advent of new machines with more detectors and higher temporal resolution has been a reduction in radiation dose and the possibility of new applications. (author)

  13. Linfoma renal: espectro de imagens na tomografia computadorizada Renal lymphoma: spectrum of computed tomography findings

    Directory of Open Access Journals (Sweden)

    Carol Pontes de Miranda Maranhão

    2005-04-01

    Full Text Available O acometimento renal no linfoma é raro, uma vez que o rim não possui tecido linfóide. O envolvimento secundário é mais freqüente, ocorrendo em até um terço das autópsias dos portadores de linfoma. Alguns autores acreditam que esta seja a única forma de acometimento renal, questionando a existência do linfoma primário. O linfoma renal representaria metástases hematogênicas ou invasão direta do tumor ocorrendo no espaço perirrenal. A partir destes tipos de envolvimento decorrem as formas de apresentação do linfoma renal: múltiplos nódulos, massa solitária, invasão renal por doença retroperitoneal contígua, doença perirrenal e infiltração difusa. Neste trabalho são discutidas e apresentadas imagens destas diferentes formas de acometimento.Isolated renal lymphoma is rare due to the absence of lymphoid tissue in kidneys. Secondary involvement occurs more frequently and is reported in up to 1/3 of the autopsies of patients who died from lymphoma. Some authors believe this is actually the only existing form of renal lymphoma. The involvement of the kidney by lymphoma would occur through hematogenic metastasis or direct tumor invasion of the perirenal space. These different types of involvement determine the several forms of renal lymphoma presentation: multiple nodules, solitary mass, renal invasion from contiguous retroperitoneal disease, perirenal disease and diffuse infiltration. In this study the imaging findings features of the different forms of involvement are presented and discussed.

  14. Dose evaluation in diagnostic for computerized tomography; Evaluacion de dosis en diagnostico por tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Flores, W.; Borges, J.C.; Mota, H. [Universidad Federal de Rio de Janeiro, PEN/COPPE/UFRJ. Caixa Postal 68509. 21945-970 Rio de Janeiro (Brazil)

    1998-12-31

    The patients which are subjected to computerized tomography tests are exposed to relatively high doses given as result doses on organs that are not matter to test. It was realized a dose levels raising in patients subjected to tests by T C, utilizing to measure this magnitude, TLD-100 thermoluminescent dosemeters which were put directly on the patient, in eye regions, thyroid, breast and navel; founding doses fluctuating between 29.10-49.39 mGy in organs examined and dose values between 0.21-29.10 mGy for organs that no matter to test. The applications of ionizing radiations in medicine do not have dose limits, but paying attention to the radiological protection optimization principle, it is recommended the use of clothes to anti-rays protection for zones not examined, getting with this to reduce the level doses as low as possible, without this to diminish the test quality. (Author)

  15. Thermoluminescent dosimetry in computed tomography for pediatric patients; Dosimetria termoluminiscente en tomografia computada para pacientes pediatricos

    Energy Technology Data Exchange (ETDEWEB)

    Medrano S, A. C.; Medina A, O.; Hidalgo T, S.; Azorin N, J., E-mail: alicesar1993@hotmail.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)

    2015-10-15

    Computed tomography (CT) in conjunction with interventional radiology, is considered as high-dose radiological procedure, so the optimization of the dose is necessary. Exposure to ionizing radiation in pediatric CT is of particular interest because the children are up to 10 times more sensitive to radiation than adults, the late somatic and genetic effects of radiation. The exposure and risk associated with ionizing radiation in CT is best characterized by the absorbed dose to each organ. Thermoluminescent dosimeters of LiF: Mg, Ti are best suited for this purpose due to its characteristics such as high sensitivity, small size and its equivalence with the tissue. The results of dose measurements -in vivo- to the three types of CT studies (skull, thorax and abdomen) are presented. These results indicate that lower doses were obtained in skull study, while the highest was one of abdomen. (Author)

  16. Computed tomography study of otitis media; A tomografia computadorizada no estudo das otites medias

    Energy Technology Data Exchange (ETDEWEB)

    Bahia, Paulo Roberto Valle; Marchiori, Edson [Universidade Federal, Rio de Janeiro, RJ (Brazil). Dept. de Radiologia

    1997-03-01

    The findings of computed tomography (CT) of 89 patients clinically suspected of having otitis media were studied in this work. Such results were compared to clinical diagnosis, otoscopy, surgical findings and previous data. Among the results of our analysis, we studied seven patients with acute otitis media and 83 patients with chronic otitis media. The patients with acute otitis media have undergone CT examinations to evaluate possible spread to central nervous system. The diagnosis of cholesteatoma, its extension and complications were the main indication. for chronic otitis media study. The main findings of the cholesteatomatous otitis were the occupation of the epitympanun, the bony wall destruction and the ossicular chain erosion. The CT demonstrated a great sensibility to diagnose the cholesteatoma. (author) 25 refs., 10 figs.

  17. Quality index on computed tomography; Índice da qualidade em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Travassos, P.C.B.; Magalhães, L.A.G., E-mail: pctravassos@gmail.com [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Peixoto, J.G.P. [Universidade do Estado do Rio de Janeiro (LCR/UERJ), RJ (Brazil)

    2017-07-01

    Quality analysis was carried out from Indicators divided into 3 sectors: Regulation and Management; Equipment; Image Quality and Dosimetry. Values were assigned for each indicator according to the degree of compliance with the specifications, and were used to calculate the Index. The model was applied in 110 institutions of the State of Rio de Janeiro, and the results were distributed into 5 ranges of values. About 40% of the institutions received grades belonging to the two highest ranges of values. There was no significant difference between the results of old scanners compared to the younger ones. (author)

  18. Dose determination in computed tomography; Determinacion de dosis en tomografia computada

    Energy Technology Data Exchange (ETDEWEB)

    Descamps, C.; Garrigo, E.; Venencia, D. [Fundacion Marie Curie, Instituto Privado de Radioterapia, Departamento de Fisica Medica, Obispo Oro 423, X5000BFI Cordoba (Argentina); Gonzalez, M. [Universidad Nacional de Cordoba, Facultad de Ciencias Exactas, Fisicas y Naturales, Av. Velez Sarsfield 299, Corboba (Argentina); Germanier, A., E-mail: agermani@ceprocor.uncor.edu [Ministerio de Ciencia y Tecnologia, Ceprocor, Alvarez de Arenas 230, X5004AAP Barrio Juniors, Cordoba (Argentina)

    2011-10-15

    In the last years the methodologies to determine the dose in computed tomography have been revised. In this work was realized a dosimetric study about the exploration protocols used for simulation of radiotherapy treatments. The methodology described in the Report No. 111 of the American Association of Medical Physiques on a computed tomograph of two cuts was applied. A cylindrical phantom of water was used with dimensions: 30 cm of diameter and 50 cm of longitude that simulates the absorption and dispersion conditions of a mature body of size average. The doses were determined with ionization chamber and thermoluminescent dosimetry. The results indicate that the dose information that provides the tomograph underestimates the dose between 32 and 35%.

  19. Computed Tomography of the diabetic kidney; La Tomografia Computerizzata nello studio del rene diabetico

    Energy Technology Data Exchange (ETDEWEB)

    Angelelli, G.; Stabile Ianora, A.A.; Scardapane, A.; Rotondo, A. [Bari Univ., Bari (Italy). Ist. di Radiologia

    2000-02-01

    The purpose of this work is to investigate whether any morphometric or densitometric are detectable in the kidneys of type 2 diabetic patients. 40 diabetic patients were examined and of 20 non-diabetics (the control group) were submitted to triphasic helical CT for different abdominal conditions. The type 2 diabetic patients were 23 men and 17 women, mean age 62 years, while the nondiabetic controls were 12 men and 8 women, mean age 58 years. All the CT images were analyzed using the Multiplanar Reconstruction (MPR) software. It was evaluated morphometric features, such as the presence of parenchymal or vascular calcifications, axial and coronal renal diameters, coronal renal area, and cortico medullary ratio, and densitometric and functional features, such as unenhanced renal density, cortical and medullary density in the arterial phase, parenchymal density in the nephrographic phase, and contrast elimination. It was also compared the results in the subgroups of patients with those in the controls. Both renal diameters on axial sections and cortical density in the arterial phase were significantly lower in the nephropathic group (p<0.05) than in non-nephropathic patients and control. The patients with shorter duration of their diabetes had significantly greater axial diameters (p<0.05); a longer-standing disease correlated significantly (p<0.05) with smaller axial diameters of kidneys and lower cortical density in the arterial phase. Renal diameters on axial and coronal sections and cortical density in the arterial phase can be useful indices of early nephropathy in diabetic patients. Further studies are warranted to make these findings suitable for use in clinical practice. [Italian] In questo articolo sono presentate le eventuali alterazioni tomodensitometriche a livello renale di pazienti affetti da diabete mellito di tipo 2. Si sono valutate retrospettivamente le immagini TC di 40 soggetti affetti da diabete di tipo 2 (23 maschi, 17 femmine, eta' media 62 anni) e di 20 soggetti sani (12 maschi, 8 femmine, eta' media: 58 anni). Lo studio TC e' stato eseguito con tecnica spirale trifasica; i dati acquisiti sono stati successivamente trasferiti su una stazione di lavoro ed analizzati con il software applicativo Multiplanar Reconstruction (MPR) che ha permesso ricostruzioni secondo piani assiale e coronale. Si sono considerati i parametri morfometrici (presenza di calcificazioni parenchimali e/o vascolari, dimensioni del rene nelle sezioni assiale e longitudinale, superficie renale in sezione longitudinale, rapporto cortico-midollare), densitometrici (densita' renale senza mdc, densita' della corticale e della midollare nella fase arteriosa, densita' nella fase tubulonefrografica) e funzionali (omogeneo incremento di densita' in fase tubulonefrografica e presenza della fase escretoria) e confrontato i valori ottenuti nei vari sottogruppi di pazienti diabetici e nel gruppo di controllo. Le dimensioni renali nella sezione assiale sono risultate significativamente inferiori (p<0,05) nei pazienti con durata minore del diabete presentavano reni significativamente piu' grandi nella sezione assiale rispetto agli altri gruppi; tali dimensioni si riducevano significativamente nel gruppo con durata piu' lunga della malattia. La valutazione delle dimensioni renali e soprattutto della riduzione della densita' della corticale renale nella fase arteriosa puo' essere utile come indice di nefropatia nei pazienti diabetici non insulino dipendenti. Ulteriori ricerche sono tuttavia necessarie per raggiungere validi protocolli utilizzabili nella pratica quotidiana.

  20. Aspectos da tomografia computadorizada craniana na neurocisticercose na infância

    Directory of Open Access Journals (Sweden)

    Marilisa M. Guerreiro

    1989-06-01

    Full Text Available Os autores relatam aspectos tomográficos da neurocisticercose na infância a propósito da análise de 27 exames em 18 pacientes, que foram distribuídos em três grupos segundo o quadru clínico e os achados tomográficos. O grupo 1 foi caracterizado basicamente por epilepsias e calcificações. O grupo 2 caracterizou-se por hipertensão intracraniana e diversos aspectos tomográficos: edema, cistos e nódulos em três pacientes; hidrocefalia e calcificações em dois pacientes e normal em um paciente. O grupo 3 consistiu clinicamente de epilepsia e cefaléia, com vários padrões tomográficos. Os resultados são discutidos à luz da literatura disponível.

  1. Cerebral toxoplasmosis in AIDS - computerized tomography evaluation; Toxoplasmose cerebral na SIDA - avaliacao por tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Regina Coeli Fonseca [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Hospital Universitario Antonio Pedro. Servico de Radiologia; Narchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia

    1999-06-01

    Cerebral toxoplasmosis is a disease that affects many AIDS's patients. FOr this paper 46 patients with confirmed cases of cerebral toxoplasmosis who did a CT scan between March, 1994 and September, 1997 were examined. Single lesions were found in 28.3% of the patients. The lesions were more frequently detected in the basal ganglia and the frontal lobes. No lesion was larger than 4 cm. As regards the contrast enhancing of the lesions on a CT scan we observed that 54.5% of the lesions had a ring-like contrast enhancing, 36.4% had a nodular contrast enhancing and 6% had a heterogeneous form. After the 21st day of treatment we noticed an improvement in the aspect of the patients'lesions. The improvement of the lesions could be seen through a reduction of the edematous halo, a reduction of the lesion size and a modification in the contrast enhancing on the CT scan. The CT scan was an important method to demonstrate the lesions compatibility enhancing on the CT scan. The CT scan was an important method to demonstrate the lesions compatibility with cerebral toxoplasmosis, as well as to monitor these patients during treatment. (author)

  2. Reconstrução tridimensional de arcos magnéticos por tomografia

    Science.gov (United States)

    Simões, P. J. A.; Costa, J. E. R.

    2003-08-01

    Uma explosão solar é uma variação súbita do brilho que ocorre nas regiões ativas da atmosfera solar. Estas regiões são constituídas por um plasma magnetizado com intensa indução magnética e em cenários bem complexos como visto recentemente através de experimentos embarcados em satélites operando instrumentos em raios X moles e ultra-violeta distante. A energia magnética, que pode ser armazenada por um período de horas até dias em configurações magnéticas estressadas, é subitamente lançada na atmosfera solar e transferida para partículas como elétrons, prótons e núcleos pesados, que são acelerados e/ou aquecidos, produzindo radiação eletromagnética. A proposta final deste projeto é determinar as características espaciais de alta resolução da emissão e polarização girossincrotrônica de explosões solares em ambientes complexos de campos magnéticos. Os recentes resultados da emissão difusa em EUV apresentado pelos satélites TRACE e SOHO dos arcos magnéticos conectando as diferentes polaridades magnéticas sobre as regiões ativas possibilitam novas abordagens sobre o papel do campo magnético na emissão em rádio. Nesta etapa apresentamos os resultados da reconstrução da geometria tridimensional das linhas de força destes arcos utilizando técnicas tomográficas, a partir de imagens de alta resolução espacial obtidas pelo instrumento EIT (Extreme ultraviolet Imaging Telescope), além da modelagem das induções magnéticas por um campo dipolar e as densidades de partículas aceleradas. Utilizamos para a reconstrução geométrica, imagens tomadas em vários ângulos dos arcos devido à rotacão solar. Com estes resultados, daremos continuidade ao projeto, com os cálculos da transferência radiativa nos modos ordinário e extraordinário de propagação da radiação girossincrotrônica de explosões solares.

  3. CT in the evaluation of severe liver trauma; Tomografia computadorizada na avaliacao do trauma hepatico grave

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Marcel Autran C. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina, Hospital das Clinicas; Souza Rocha, Manoel de; Machado, Manoel C.C. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina; Macedo Neto, Augusto Cesar de; Maciel, Rosangela Pereira; Simonetti, Celso

    1995-05-01

    Abdominal CT is a common examination in the evaluation of patients with blunt abdominal trauma and clinical suspicion for solid organ injury when reasons for immediate laparotomy are not present. A case of major blunt hepatic injury in a 22-year-old patient is reported. The authors present a brief review of the literature and discussion about the role of CT scan in the evaluation of hepatic trauma, surgical planning and postoperative follow-up. (author). 15 refs., 3 figs., 1 tab.

  4. Technical competence in cardiovascular magnetic resonance and computed tomography; Competencia tecnica em ressonancia e tomografia cardiovascular

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Juliano Lara; Shiozaki, Afonso Akio; Azevedo Filho, Clerio Francisco de; Rochitte, Carlos Eduardo; Pinto, Ibraim Marciarelli Francisco; Lopes, Marly Maria Uellendahl; Schvartzman, Paulo Roberto, E-mail: jlaraf@fcm.unicamp.br [Universidade de Campinas (UNICAMP/GERT) SP (Brazil). Grupo de Estudo em Ressonancia e Tomografia Cardiovascular

    2009-10-15

    Cardiovascular magnetic resonance and computed tomography have evolved as very practical and useful techniques applied in clinical cardiology. Due to their rapid acceptance in the cardiology community and widespread use, training of both cardiologists and radiologists on this subspecialty has not been homogeneous so far. This in part explains significant differences observed in the diverse background found in today’s practicing physicians who execute these exams. In order to guide training facilities as well as both payers, contractors and general cardiologists ordering the exam, this document provides a minimum standard that should be accomplished by all physicians who pursue education in the field and for those who already practice in it. The clinical competences listed in this statement are by no means thorough but should be required by all those involved in cardiovascular magnetic resonance and computed tomography as the customary requirements for current and future practitioners. (author)

  5. Computed tomography evaluation of mast cell tumours; Avaliacao por tomografia computadorizada dos mastocitomas

    Energy Technology Data Exchange (ETDEWEB)

    Lorigados, Carla Aparecida Batista; Matera, Julia Maria; Macedo, Thais; Pinto, Ana Carolina Brandao Fonseca, E-mail: clorigados@usp.br [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia. Dept. de Cirurgia

    2012-07-01

    The mast cell tumours are common tumours of the canine skin. Computed tomography (CT) has assumed an important role in tumours evaluation and staging. The aim of this study was to evaluate the role of CT as a method of assessing characteristics of mast cell tumors. Ten dogs with mast cell tumor were evaluated. CT was performed before and after the intravenous injection of hydro soluble ionic iodine. Attenuation, contrast enhancement, cleavage with adjacent tissues and the unidimensional measurement of each lesion was determined in it maximum diameter, in transversal plane. Concerning the attenuation characteristic, 50% were homogeneous and 50% heterogeneous. The contrast enhancement was homogeneous in 50% of cases, heterogeneous in 40% and peripheral in 10%. Fifty percent of the tumours showed loss of plane of cleavage and 30% partial loss. This information can help in directing the patients that will be undergoing chemotherapy or surgery. (author)

  6. Dose assessment in pediatric computerized tomography; Avaliacao de doses em tomografia computadorizada pediatrica

    Energy Technology Data Exchange (ETDEWEB)

    Vilarinho, Luisa Maria Auredine Lima

    2004-07-01

    The objective of this work was the evaluation of radiation doses in paediatric computed tomography scans, considering the high doses usually involved and the absence of any previous evaluation in Brazil. Dose values were determined for skull and abdomen examinations, for different age ranges, by using the radiographic techniques routinely used in the clinical centers investigated. Measurements were done using pencil shape ionization chambers inserted in polymethylmethacrylate (PMMA) phantoms. These were compact phantoms of different diameters were specially designed and constructed for this work, which simulate different age ranges. Comparison of results with published values showed that doses were lower than the diagnostic reference levels established to adults exams by the European Commission. Nevertheless, doses in paediatric phantoms were higher than those obtained in adult phantoms. The paediatric dose values obtained in Hospitals A and B were lower than the reference level (DRL) adopted by SHIMPTON for different age ranges. In the range 0 - 0.5 year (neonatal), the values of DLP in Hospital B were 94 por cent superior to the DRL For the 10 years old children the values of CTDI{sub w} obtained were inferior in 89 por cent for skull and 83 por cent for abdomen examinations, compared to the values published by SHRIMPTON and WALL. Our measured CTDI{sub w} values were inferior to the values presented for SHRIMPTON and HUDA, for all the age ranges and types of examinations. It was observed that the normalized dose descriptors values in children in the neonatal range were always superior to the values of doses for the adult patient. In abdomen examinations, the difference was approximately 90% for the effective dose (E) and of 57%.for CTDI{sub w} . (author)

  7. Avaliação pulmonar em crianças portadoras de cardiopatia congênita acianótica e hiperfluxo pulmonar através de tomografia computadorizada Evaluación pulmonar en niños portadores de cardiopatía congénita acianótica e hiperflujo pulmonar a través de tomografía computadorizada Computed tomography in pulmonary evaluation of children with acyanotic congenital heart defect and pulmonary hyperflow

    Directory of Open Access Journals (Sweden)

    Solange Gimenez

    2009-10-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Disfunção respiratória é frequente em crianças com cardiopatias congênitas acianóticas com hiperfluxo pulmonar (CCAHP, porém pouco é conhecido sobre a estrutura pulmonar destes pacientes. O objetivo deste estudo foi quantificar os volumes de gás e tecido e a distribuição da aeração pulmonar nesta população. MÉTODOS: Após aprovação do Comitê de Ética institucional e obtenção do consentimento escrito pós-informado, foram obtidas tomografias computadorizadas torácicas em sete crianças com CCAHF. As imagens pulmonares direita e esquerda foram contornadas em todas as imagens e os volumes e pesos pulmonares foram computados a partir dos dados volumétricos. As comparações entre esquerda e direita foram analisadas usando teste t de Student pareado e as correlações através de regressão exponencial. RESULTADOS: A idade mediana foi 20 meses e o peso foi de 9,9 kg. Volume pulmonar total (VPT foi de 66,7 ± 23,1 mL.kg-1, o de tecido 33,5 ± 15,7 mL.kg-1 e o de gás 33,1 ± 8,3 mL.kg-1. O pulmão direito representou 57,9% e o pulmão esquerdo 42,1% do VPT (p JUSTIFICATIVA Y OBJETIVOS: La disfunción respiratoria es frecuente en niños con cardiopatías congénitas acianóticas con hiperflujo pulmonar (CCAHP, sin embargo, se conoce muy poco sobre la estructura pulmonar de esos pacientes. El objetivo de este estudio, fue cuantificar los volúmenes de gas y tejido y la distribución de la aeración pulmonar en esa población. MÉTODOS: Después de la aprobación por parte del Comité de Ética Institucional y de la obtención del consentimiento escrito informado, se obtuvieron tomografías computadorizadas torácicas en siete niños con CCAHF. Las imágenes pulmonares derecha e izquierda fueron perfiladas en todas las imágenes, y los volúmenes y los pesos pulmonares fueron computados a partir de los datos volumétricos. Las comparaciones entre izquierda y derecha fueron analizadas usando el test t de

  8. Process and device to set a separated helicoid thread in a large diameter tapped hole and use of this process and device

    International Nuclear Information System (INIS)

    Dworaczek, J.P.; Grypczynski, D.

    1992-01-01

    In a PWR reactor the vessel head is fixed to the reactor vessel by the vessel flange and closure studs. If the thread machined in the vessel flange is damaged or worn out, a separate thread, rolled up on a tapped drum is screwed in the tapped opening and the thread is fixed by a pin

  9. Heat transfer and critical heat flux in a spiral flow in an asymmetrical heated tube; Transfert thermique et flux critique dans un ecoulement helicoidal en tube chauffe asymetriquement

    Energy Technology Data Exchange (ETDEWEB)

    Boscary, J [CEA Centre d` Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Direction des Sciences de la Matiere; [Association Euratom-CEA, Centre d` Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee

    1997-03-01

    The design of plasma facing components is crucial for plasma performance in next fusion reactors. These elements will be submitted to very high heat flux. They will be actively water-cooled by swirl tubes in the subcooled boiling regime. High heat flux experiments were conducted in order to analyse the heat transfer and to evaluate the critical heat flux. Water-cooled mock-ups were one-side heated by an electron beam gun for different thermal-hydraulic conditions. The critical heat flux was detected by an original method based on the isotherm modification on the heated surface. The wall heat transfer law including forced convection and subcooled boiling regimes was established. Numerical calculations of the material heat transfer conduction allowed the non-homogeneous distribution of the wall temperature and of the wall heat flux to be evaluated. The critical heat flux value was defined as the wall maximum heat flux. A critical heat flux model based on the liquid sublayer dryout under a vapor blanket was established. A good agreement with test results was found. (author) 197 refs.

  10. Diagnóstico do embolismo pulmonar

    Directory of Open Access Journals (Sweden)

    João Castaño

    2003-03-01

    Full Text Available RESUMO: O diagnóstico do Embolismo Pulmonar é considerado por vezes difícil. É importante reconhecer as situações clínicas que podem ser potencialmente desencadeantes. Existe uma série de meios auxiliares de diagnóstico, quer laboratoriais quer imagiológicos, que devem ser adaptados aos meios disponíveis em cada instituição.REV PORT PNEUMOL 2003; IX (2: 129-137 ABSTRACT: Pulmonary Embolism is often considered a difficult diagnosis to establish. It is important to recognise clinical situations that leads to it. There are a few laboratory and imaging tests, that should be tailored to the available facilities in each institution.REV PORT PNEUMOL 2003; IX (2: 129-137 Palavaras-chave: Tromboembolismo Pulmonar, Pulmão, Perfusão Pulmonar, Tomografia Computorizada (TC, Angiografia, Helicoidal, Key-words: Pulmonary Embolism, Lung, Lung Perfusion, Computed Tomography (CT, Angiography, Helical

  11. Evaluation of ambient radiation levels in positron emission tomography/computed tomography in microPET/CT laboratory; Avaliacao dos niveis de radiacao ambiental no laboratorio de tomografia por emissao de positrons acoplada a tomografia computadorizada, microPET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Sarmento, Daniele Martins

    2016-11-01

    Micro PET/CT scanner is an essential tool generally used for small animal molecular imaging. Fluorine-18-labeled fluorodeoxyglucose is the most widely used radioisotope in this technique. The present study aimed to evaluate the radiation levels in a micro PET/CT research laboratory of the Radiopharmacy Center at IPEN-CNEN / SP, in order to accomplish both national standards and international recommendations. The radioprotection team has classified the laboratory as supervised area; even this laboratory does not require the adoption of specific measures for protection and safety, should be done regular re-evaluation of the conditions of occupational exposures. Workplace monitoring and individual control assessment were carried out to ensure the radiological protection of all workers directly involved in handling the scanner. Initially, there was conducted a radiometric survey, as well as measurements of the external radiation level in the workplace and its surroundings. To achieve this goal, there were placed nine thermoluminescent dosimeters of CaSO{sub 4}:Dy in preselected locations. Monthly evaluations of the occupationally exposed individuals were carried out through the use of TL dosimeters, ported in the workers' chest. Moreover, whole body measurements were performed every six months. The study period was about two-years which started in April 2014. All tests to evaluate micro PET/CT performance were based on the standard protocol of the equipment in accordance with the standard developed by the Animal PET Standard Task Force. Present study's results demonstrated that the ambient radiation levels (ambient and effective estimated radiation dose), as well as the effective shielding equipment are both adequate. This study emphasizes that it is essential to strictly follow the principles of radioprotection in workplace, whenever researches involve radioactive unsealed sources. (author)

  12. Positron Emission Tomography (PET) in the oncologic clinical practice; Tomografia por Emision de Positrones (PET) en la practica clinica oncologica

    Energy Technology Data Exchange (ETDEWEB)

    Serna M, J A; Luviano, C; Martinez V, D [Hospital Angeles del Pedregal Mexico DF (Mexico); Maldonado S, A [Centro PET Complutense, Madrid (Spain)

    2005-07-01

    We intended to determine the frequency with that the computer axial tomography (TAC), it was able to visualize the lesions extra neoplasia detected by the PET tomography in patients with fully identified primary malignant neoplasia. (Author)

  13. AIDS related thoracic lymphoma: evaluation by computed tomography; Linfoma toracico na sindrome da imunodeficiencia adquirida: avaliacao por tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Siciliano, Antonio Alexandre de Oliveira [Hospital Universitario Clementino Fraga Filho, Rio de Janeiro, RJ (Brazil). Servico de Radiodiagnostico; Marchiori, Edson [Universidade Federal, Rio de Janeiro, RJ (Brazil). Curso de Pos-graduacao em Radiologia

    2000-02-01

    The authors reviewed five cases of patients with acquired immunodeficiency syndrome (AIDS) related lymphoma to describe the thoracic findings on computed tomography. The patients were followed at Hospital Universitario Clementino Fraga Filho, Hospital Universitario Antonio Pedro and Hospital da Lagoa, from November, 1989 to March 1998. Epidemiological, clinical and pathological data from these patients were quiet variable and pulmonary nodules and masses, hilar and mediastinal lymphadenopathy, and thoracic wall masses were observed. AIDS related lymphomas involving the chest are pleomorphic and most commonly extranodal. (author)

  14. Tomografia de coerência óptica na distrofia corneana gelatinosa em gotas: relato de caso

    OpenAIRE

    Magalhães, Otávio de Azevedo; Rymer, Samuel; Marinho, Diane Ruschel; Kwitko, Sérgio; Cardoso, Isabel Habeyche; Kliemann, Lúcia

    2012-01-01

    Gelatinous drop-like corneal dystrophy is a rare disorder with few cases described in the present literature. The following report will show how difficult it is to diagnose this disease in early stages. Modern image exams, such as optical coherence tomography helps to diagnose and can be crucial to establish the best treatment. We will present the histopathological changes and clinical features in this unusual dystrophy.A distrofia corneana gelatinosa em gotas é uma desordem rara e pouco desc...

  15. Wegener's granulomatosis: chest computed tomography findings; Granulomatose de Wegener: aspectos na tomografia computadorizada de torax

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, Evelise de Azevedo; Marchiori, Edson; Martins, Erick Malheiro Leoncio [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia]. E-mail: edmarchiori@zipmail.com.br; Souza Junior, Arthur Soares [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Hospital de Base; Cerqueira, Elza Maria F.P. de [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Radiologia; Irion, Klaus L. [Pavilhao Pereira Filho, Porto Alegre, RS (Brazil); Araujo Neto, Cesar de [Bahia Univ., Salvador, BA (Brazil). Dept. de Radiologia; Souza, Rodrigo Azeredo de [Universidade Federal, Rio de Janeiro, RJ (Brazil). Faculdade de Medicina. Dept. de Radiologia

    2003-03-01

    Wegeners granulomatosis is an inflammatory systemic necrotizing idiopathic vasculitis affecting mainly small vessels. In this paper we analyzed the computed tomography findings of seven patients with Wegeners granulomatosis. The most common findings were masses and nodules (71.4%), areas of ground glass attenuation (57.1%), consolidation (42.8%), halo sign (42.8%), cavitation (42.8%), interlobular septa thickening (14.2%), bronchial wall thickening (14.2%) and pleural effusion (14.2%). Although radiological findings are mostly nonspecific, computed tomography and particularly high-resolution computed tomography are important tools in the evaluation of disease activity when evaluated in association with bronchoscopy findings and clinical data. (author)

  16. Development of a guidance guide for dosimetry in computed tomography; Desenvolvimento de um guia orientativo para dosimetria em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Fontes, Ladyjane Pereira

    2016-07-01

    Due to frequent questions from users of ionization chambers pencil type calibrated in the Instrument Calibration Laboratory of the Institute of Energy and Nuclear Research (LCI - IPEN), on how to properly apply the factors indicated in their calibration certificates, a guide was prepared guidance for dosimetry in computed tomography. The guide includes guidance prior knowledge of half value layer (HVL), as it is necessary to know the effective beam energy for application quality for correction factor (kq). The evaluation of HVL in TC scanners becomes a difficult task due to system geometry and therefore a survey was conducted of existing methodologies for the determination of HVL in clinical beams Computed Tomography, taking into account technical, practical and economic factors. In this work it was decided to test a Tandem System consists of absorbing covers made in the workshop of IPEN, based on preliminary studies due to low cost and good response. The Tandem system consists of five cylindrical absorbing layers of 1mm, 3mm, 5mm, 7mm and 10mm aluminum and 3 cylindrical absorbing covers 15mm, 25mm and acrylic 35mm (PMMA) coupled to the ionization chamber of commercial pencil type widely used in quality control tests in dosimetry in clinical beams Computed tomography. Through Tandem curves it was possible to assess HVL values and from the standard curve pencil-type ionization chamber, Kq find the appropriate beam. The elaborate Guide provides information on how to build the calibration curve on the basis of CSR, to find the Kq and information for construction Tandem curve, to find values close to CSR. (author)

  17. Nonoperative treatment of splenic trauma: usefulness of computed tomography; Tratamento conservador do trauma esplenico: utilidade da tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Resende, Vivian [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Faculdade de Medicina; Tavares Junior, Wilson Campos; Vieira, Jose Nelson Mendes [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Hospital das Clinicas. Dept. de Radiologia e Diagnostico por Imagem]. E-mail: wilsontavaresjrmd@yahoo.fr; Drumond, Domingos Andre Fernandes [Hospital Joao XXIII, Belo Horizonte, MG (Brazil). Setor de Clinica Cirurgica

    2005-04-15

    Objective: to report the results of use of conservative treatment in patients with splenic trauma and to emphasize the usefulness of computed tomography in these cases. Material and method: sixty-nine cases of pediatric patients with blunt abdominal trauma seen from from January 2001 to June 2004 at the level I trauma center were retrospectively studied. Forty-four of these patients were submitted to nonoperative treatment and the clinical follow-up was performed by computerized tomography. All patients had been diagnosed with splenic injury by computerized tomography.Results: the causes of the injuries were motor vehicle accident in 12 (27.2%) patients, bicycle accident in nine (20.4%) patients, and falls in 23 (52.2%) patients. Two (3.7%) patients died from associated injuries. The mean duration of hospital stay was six days. The mean age of the patients was nine years. Conclusion: conservative treatment for blunt splenic trauma is performed with the aim of reducing costs and risks for the patients, and computerized tomography should be routinely used. No posterior complications were observed in this approach. (author)

  18. Use of positron emission tomography in colorectal cancer; Uso de la tomografia de emision de positrones en el cancer colorrectal

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez E, Patricio; Jofre E, Josefina; Massardo V, Teresa; Humeres, Pamela; Canessa G, Jose; Sierralta C, Paulina [Hospital Militar de Santiago, Medicina Nuclear, Centro PET de Imagenes Moleculares, Santiago (Chile)

    2002-07-01

    The value of PET (Positron Emission Tomography) in colorectal cancer is presented. PET is a novel technique that uses F-18-FDG (fluorodeoxiglucose) to assess glucose metabolism by whole body imaging. It has been demonstrated that malignant cells have both increase of glucose uptake and utilization. In colorectal cancer, PET is indicated for staging, assess recurrence, liver metastasis and treatment follow-up. PET is more sensitive and specific than CT (Computed Tomography) and is cost effective. In 30% of cases PET may change patient management, avoiding unnecessary procedures (au)

  19. PET, Positron emission tomography: Presentation of a clinical case; PET, Tomografia por emision de positrones: Presentacion de un caso clinico

    Energy Technology Data Exchange (ETDEWEB)

    Sierralta C, Paulina; Jofre M, M Josefina; Gonzalez E, Patricio; Massardo V, Teresa; Humeres A, Pamela; Canessa G, Jose [Hospital Militar de Santiago, Servicio de Medicina Nuclear, Centro PET de Imagenes Moleculares, Santiago (Chile)

    2003-07-01

    A patient with a solitary pulmonary nodule is presented. She was studied with PET using F-18 FDG. The metabolic images demonstrated increased uptake in the nodule and 2 additional areas suggestive of extension, not seen in anatomic diagnostic procedures. These findings were compatible with a malignant tumour with metastasis (au)

  20. X-ray detectors in axial computed tomography development; Sensori di radiazioni X negli sviluppi della tomografia assiale computerizzata

    Energy Technology Data Exchange (ETDEWEB)

    Gislon, R.; Imperiali, F. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dip. Innovazione

    1996-12-01

    The increase of potentially of axial computed tomography as a non destructive investigation method in industrial field is particularly tied to the development of the X-rays detectors. The transition from the first gas ionization detectors to the last semiconductor detectors has indeed dramatically increased the performances of tomographic systems. In this report, after a quick analysis of fundamental principles of tomography, the most significant parameters for a detector to be used in a tomographic system are reviewed. The examination of the principal kinds of detectors that have been up to now used, with their working schemes, allows to delineate their characteristics and so to compare them with the ideal detector sketched above. The necessity of using high definition arrays brings to put into evidence the inadequacy of both gas and liquid ionization detectors and also of those types of light conversion devices which utilize for signal amplification a photomultiplier tube. Systems based on charge coupled devices or on a light conversion obtained with semiconductor photodiode arrays are definitely to be preferred. The progress of the last years in microelectronic technologies has brought great improvements in this field.

  1. Evaluation of the absorbed dose in odontological computerized tomography; Avaliacao da dose absorvida em tomografia computadorizada odontologica

    Energy Technology Data Exchange (ETDEWEB)

    Legnani, Adriano; Schelin, Hugo R.; Rocha, Anna Silvia P.S. da, E-mail: schelin@utfpr.edu.b, E-mail: anna@utfpr.edu.b [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Khoury, Helen J., E-mail: khoury@ufpe.b [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2011-10-26

    This paper evaluated the absorbed dose at the surface entry known as 'cone beam computed tomography' (CBCT) in odontological computerized tomography. Examination were simulated with CBCT for measurements of dose. A phantom were filled with water, becoming scatter object of radiation. Thermoluminescent dosemeters were positioned on points correspondent to eyes and salivary glands

  2. Evaluation of the absorbed dose in odontological computerized tomography; Avaliacao da dose absorvida em tomografia computadorizada odontologica

    Energy Technology Data Exchange (ETDEWEB)

    Legnani, Adriano; Schelin, Hugo R; Rocha, Anna Silvia P.S. da, E-mail: schelin@utfpr.edu.b, E-mail: anna@utfpr.edu.b [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Khoury, Helen J., E-mail: khoury@ufpe.b [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2011-10-26

    This paper evaluated the absorbed dose at the surface entry known as 'cone beam computed tomography' (CBCT) in odontological computerized tomography. Examination were simulated with CBCT for measurements of dose. A phantom were filled with water, becoming scatter object of radiation. Thermoluminescent dosemeters were positioned on points correspondent to eyes and salivary glands

  3. Soil structure changes evaluated with computed tomography;Mudancas na estrutura do solo avaliada com uso de tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Pires, Luiz Fernando [Universidade Estadual de Ponta Grossa (UEPG), PR (Brazil). Dept. de Fisica; Bacchi, Osny Oliveira Santos, E-mail: osny@cena.usp.b [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

    2010-04-15

    The objective of this work was to evaluate in millimetric scale changes in soil bulk density and porosity, using the gamma-ray computed tomography in soil samples with disturbed structure due to wetting and drying (W-D) cycles. Soil samples with 98.1 cm{sup 3} were sieved using a 2 mm mesh and homogeneously packed in PVC cylinders. Soil samples were submitted to 1, 2, and 3 W-D cycles. Control samples were not submitted to W-D cycles. After repetitions of W-D cycles, soil sample porosity decreased and soil layers became denser. Computed tomography allowed a continuous analysis of soil bulk density and also soil porosity along millimetric (0.08 cm) layers, what cannot be provided by traditional methods used in soil physics. (author)

  4. Computed Tomography findings in Fournier's gangrene; Hallazgos en tomografia computarizada de la grangrena de Fournier

    Energy Technology Data Exchange (ETDEWEB)

    Isusi, M.; Campo, M.; Oleaga, L.; Grande, J.; Grande, D. [Hospital de Barsurto. Bilbao (Spain)

    2000-07-01

    To assess the utility of computed tomography (CT) as an imaging technique in the diagnosis and determination of the extension of Fournier's gangrene (FG). We report the cases of six patients who had been clinically diagnosed as having FG, CT, enhanced by oral and intravenous contrast media, was performed in all the patients. All six patients presented soft tissue masses and gas in the scrotal region, which were also detected in the perineal region in five. In two patients, the gas extended toward anterior abdominal wall and in one of them, it also observed in anterior and posterior para renal space. The major predisposing factors were diabetes and alcoholism and the most common triggering factor was urologic disease. CT confirms the existence of FG and aids in assessing its extension and, in some cases, in identifying the underlying cause. (Author) 15 refs.

  5. Dose profile in computed tomography chest scan; Perfil de dose em varredura de torax em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Bruno B., E-mail: bbo@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Pos-graduacao em Ciencias e Tecnologia das Radiacoes, Minerais e Materiais; Mourao, Arnaldo P. [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET/MG), Belo Horizonte, MG (Brazil); Alonso, Thessa C.; Silva, Teogenes A. da [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2010-07-01

    For the optimization of the patient dose in computed tomography (CT), the Brazilian legislation only established the diagnostic reference levels (DRL's) in terms of Multiple Scan Average Dose (MSAD) in a typical adult as a parameter of quality control of CT scanners. Conformity to the DRL's can be verified by measuring the dose distribution in CT scans and MSAD determination. An analysis of the quality of CT scans of the metropolitan region of Belo Horizonte is necessary by conducting pertinent tests to the study that are presented in the ANVISA (National Agency of Sanitary Vigilance) Guide. The purpose of this study is to investigate, in a chest scan, the variation of dose in CT. To measure the dose profile are used lithium fluoride thermoluminescent dosimeters (TLD-100 Rod) distributed in cylinders positioned in peripheral and central regions of a phantom of polymethylmethacrylate (PMMA). The data obtained allow us to observe the variation of the dose profile inside the phantom. The peripheral region shows higher dose values than the central region. The longitudinal variation can be observed and the maximum dose was recorded at the edges of the phantom (41,58{+-}5,10) mGy at the midpoint of the longitudinal axis. The results will contribute to disseminate the proper procedure and optimize the dosimetry and the tests of quality control in CT, as well as make a critical analysis of the DRL's. (author)

  6. Unilateral pulmonary veins atresia: evaluation by computed tomography; Atresia unilateral das veias pulmonares: avaliacao por tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Eifer, Diego Andre; Arsego, Felipe Veras, E-mail: felipesoarestorres@gmail.com [Hospital de Clinicas de Porto Alegre (HCPA), RS (Brazil). Serv. de Radiologia; Torres, Felipe Soares [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Escola de Medicina

    2013-11-15

    Unilateral pulmonary vein atresia is a rare congenital condition. In addition to cardiac malformations or pulmonary hypertension, patients may present with recurrent pulmonary infections or hemoptysis in childhood or adolescence. The authors report a case where the typical findings of such condition were observed at computed tomography in an adult patient. (author)

  7. Pulmonary leukemic involvement: high-resolution computed tomography evaluation; Comprometimento pulmonar nas leucemias: avaliacao por tomografia computadorizada de alta resolucao

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Ana Paola de [Universidade Federal, Rio de Janeiro, RJ (Brazil). Faculdade de Medicina. Programa de Pos-graduacao em Radiologia; Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia; Souza, Junior, Arthur Soares [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Radiologia

    2004-12-01

    Objective: To evaluate the role of high-resolution computed tomography (HRCT) in patients with leukemia and pulmonary symptoms, to establish the main patterns and to correlate them with the etiology. Materials and Methods: This is a retrospective study of the HRCT of 15 patients with leukemia and pulmonary symptoms. The examinations were performed using a spatial high-resolution protocol and were analyzed by two independent radiologists. Results: The main HRCT patterns found were ground-glass opacity (n=11), consolidation (n=9), airspace nodules (n=3), septal thickening (n=3), tree-in-bud pattern (n=3), and pleural effusion (n=3). Pulmonary infection was the most common finding seen in 12 patients: bacterial pneumonia (n=6), fungal infection (n = 4), pulmonary tuberculosis (n=1) and viral infection (n=1). Leukemic pleural infiltration (n=1), lymphoma (n=1) and pulmonary hemorrhage (n=1) were detected in the other three patients. Conclusion: HRCT is an important tool that may suggest the cause of lung involvement, its extension and in some cases to guide invasive procedures in patients with leukemia. (author)

  8. Selection of multislice in nuclear magnetic resonance tomography. Selecao de multiplos planos em tomografia por ressonancia magnetica nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Frare, Junior, P L

    1990-01-01

    The study and the implementation of three techniques for the selection of multislice, aiming the optimization of the NMR tomography is presented. The first technique uses the simultaneous excitation of multiple slices, being each plane encoded with a pre determined phase for a latter decodification of the information by the linear combination of n experiments. The second one makes use of the multislice simultaneous excitation, like the first one, but the slices are acquired in the presence of an oblique reading gradient, which provides us the multi slices signal without any further computer processing. The third technique uses frequency multiplexed excitation, that is, different slices are successively excited during the repetition time of an acquisition, making possible multislice acquisition at the same time of a single slice. The construction and the use of a phantom for the equipment characterization are discussed too. Many technical aspects necessary for an improvement of the tomography performance, like reception circuits and resonators, are discussed. A brief introduction to the gradient modulated adiabatic excitation (GMAX) technique and the first results ever obtained with it, using surface coils, is presented. (author).

  9. Doses optimization to patients in computed tomography studies; Optimizacion de las dosis a pacientes en estudios de tomografia computada

    Energy Technology Data Exchange (ETDEWEB)

    Trujillo Z, F. E., E-mail: flaviotrujillo@gmail.co [Hospital Regional de Alta Especialidad de Oaxaca, Aldama s/n, Paraje El Tule, 71256 San Bartolo Coyotepec, Oaxaca (Mexico)

    2010-09-15

    in recent years the number of studies of computed tomography has been increased, as well as the technology and methodology of these, while the radiological protection to the patient has not advanced to the same step. The IAEA has implemented the Patients Radiation Protection projects, where one of the areas of more interest is the computed tomography. The present work is a brief summary of the actions to realize for the doses optimization imparted to the patients, obtaining an appropriate diagnostic quality in the images at the same time; as it was presented in the course of the project C-RLA/9/067-001. The results that were obtained between Image Quality and Dose by Radiation that is imparted to the patient are shown, as well s the exposition factors that influence in these, according to the project C-RLA/9/067-001. The main actions for the dose optimization are using tension optimized protocols (kV), of load (m As), of collimation/cut thickness, of inclination of the gantry, of the pitch/displacement by rotation, of the reconstruction algorithm (kernel), according to the diagnostic objective to reach and to the patient physical characteristics (like weight and age), as well as to use protections to shield the sensitive organs (mainly those that do not have clinical interest for the procedure). Conclusion: To establish or to begin to implement, insofar as possible, the IAEA recommendations, relating to the clinical practice of the hospitals in Mexico and to the available equipment s type. (Author)

  10. Deep benign fibrous histiocytoma: computed tomography and histology findings; Histiocitoma fibroso benigno profundo: achados na tomografia computadorizada e histologia

    Energy Technology Data Exchange (ETDEWEB)

    Farage, Luciano; Castro, Mario Augusto Padula; Macedo, Tulio Augusto Alves [Uberlandia Univ., MG (Brazil). Hospital das Clinicas. Setor de Radiologia; Salomao, Eliana Chaves; Machado, Tania Alcantara; Souza, Lincoln Pereira de; Freitas, Luiz de Oliveira [Uberlandia Univ., MG (Brazil). Faculdade de Medicina. Dept. de Clinica Medica

    2005-04-01

    We present the computed tomography images of an 83-year-old male patient with a deep benign fibrous histiocytoma at the lateral aspect of the left leg. Computed tomography images showed a well-defined mass with marked peripheral enhancement by iodinated contrast medium. Only few reports of this rare soft tissue tumor can be found in the literature. (author)

  11. Lipoid pneumonia: computed tomography findings - a case report; Pneumonia lipidica: aspectos na tomografia computadorizada - relato de caso

    Energy Technology Data Exchange (ETDEWEB)

    Farias, Janos; Martins, Erick Malheiro Leoncio; Pozes, Aline Serfaty; Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia; Fialho, Suzane Mansur [Clinica Radiologica Emilio Amorim, Rio de Janeiro, RJ (Brazil)

    2004-02-01

    The authors report a case of lipoid pneumonia in an 80 year old man with chronic constipation in regular use of mineral oil as a laxative. According to his family, he experienced coughing episodes when he took his medication. He also presented dyspnoea at rest and diminished consciousness levels. Chest radiographs showed a consolidation area in the posterior segment of right upper lobe, which did not change on successive exams. High resolution computed tomography demonstrated low-density consolidation with negative Hounsfield units (-29 to -83 UH) and ground-glass opacities in the right upper lobe and inferior lobes. These opacities predominated in the posterior regions of the lungs. The diagnosis was confirmed by the presence of oil material on bronchoalveolar washing. The patient was advised to discontinue the ingestion of mineral oil and did not return for follow-up. (author)

  12. Bone densitometry in healthy cats by quantitative computed tomography; Densitometria ossea em gatos higidos por tomografia computadorizada quantitativa

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, D.C. [Universidade Federal do Parana - Curitiba, PR (Brazil); Costa, L.A.V.S.; Teixeira, M.W.; Costa, F.S. [Universidade Federal Rural de Pernambuco - Recife, PE (Brazil); Cardoso, M.J.L. [Universidade Estadual do Norte do Parana - Campus Luiz Meneghel - Bandeirantes, PR (Brazil)

    2012-06-15

    The radiodensity of the trabecular bone of the lumbar vertebrae in 16 healthy adult cats was studied using quantitative computed tomography (QCT). The average radiodensity of the trabecular bone of the second lumbar vertebra was 436.1 +- 42.1 Hounsfield units. However, there was a nonhomogeneous radiodensity distribution of the vertebral body. (author)

  13. Aspects of pulmonary emphysema on high resolution computed tomography; Aspectos do enfisema pulmonar na tomografia computadorizada de alta resolucao

    Energy Technology Data Exchange (ETDEWEB)

    Angelo Junior, J.R.L.; Castro Lessa Angelo, M.T. de; Silva, F.M.D.; Costa, N.S.S.; Kavakama, J.; Carvalho, C.R.R.; Cerri, G.G. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina. Hospital das Clinicas

    1995-03-01

    Pulmonary emphysema is an entity characterized by enlargement of the air-space with bronchiolar walls destruction with-out evident fibrosis. It is classified according to anatomic distribution of the areas of lung destruction into these types: centrilobular, panlobular, paraseptal, and paracicatricial. TCAR is superior to chest radiographs and conventional CT is detecting these areas of pulmonary destruction. (author). 10 refs, 7 figs.

  14. Cholesteatoma: computed tomography and radiography in a dog; Colesteatoma: tomografia computadorizada e radiografia em cao com otite cronica

    Energy Technology Data Exchange (ETDEWEB)

    Belotta, Alexandra Frey; Babicsak, Viviam Rocco; Mamprim, Maria Jaqueline; Vulcano, Luiz Carlos, E-mail: a_fbelotta@yahoo.com.br [Universidade Estadual Paulista Julio de Mesquita Filho (FMVZ/UNESP), Botucatu, SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia . Dept. de Reproducao Animal e Radiologia Veterinaria; Arruda, Vanesa Kutz de; Amorim, Rogerio Martins [Universidade Estadual Paulista Julio de Mesquita Filho (FMVZ/UNESP), Botucatu, SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia. Dept. de Clinica Veterinaria

    2012-07-01

    Cholesteatoma, a rare and/or misdiagnosed disease, results of a serious complication in dogs with chronic otitis. This article describes a case of a dachshund sent to the veterinary hospital presenting signs of cognitive dysfunction associated to peripheral neuropathy of the facial nerve on the right side. At radiography, an enlargement and thickness of the contours associated with loss of anatomical definition of the right tympanic bulla compared to the left was seen. At tomography, this enlargement and thickness were seen with better definition, besides the fulfilling by hyperdense calcified content, bullae osteolysis and temporal bone sclerosis at the same side. (author)

  15. Progressive systemic sclerosis: high-resolution computed tomography findings; Esclerose sistemica progressiva: aspectos na tomografia computadorizada de alta resolucao

    Energy Technology Data Exchange (ETDEWEB)

    Gasparetto, Emerson L.; Pimenta, Rodrigo; Ono, Sergio E.; Escuissato, Dante L. [Parana Univ., Curitiba, PR (Brazil). Hospital de Clinicas. Servico de Radiologia Medica]. E-mail: dante.luiz@onda.com.br; Inoue, Cesar [Parana Univ., Curitiba, PR (Brazil). Faculdade de Medicina

    2005-09-15

    Objective: To describe the high-resolution computed tomography findings in the lung of patients with systemic sclerosis, independently of the respiratory symptoms. Materials and methods: Seventy-three high-resolution computed tomography scans of 44 patients with clinical diagnosis of systemic sclerosis were reviewed and defined by the consensus of two radiologists. Results: Abnormalities were seen in 91.8% (n = 67) of the scans. The most frequent findings were reticular pattern (90.4%), ground-glass opacities (63%), traction bronchiectasis and bronchiolectasis (56.2%), esophageal dilatation (46.6%), honeycombing pattern (28.8%) and signs of pulmonary hypertension (15.6%). In most cases the lesions were bilateral (89%) and symmetrical (58.5%). The lesions were predominantly located in the basal (91.2%) and peripheral (92.2%) regions. Conclusion: In the majority of the patients, progressive systemic sclerosis can cause pulmonary fibrosis mainly characterized by reticular pattern with basal and peripheral distribution on high-resolution computed tomography. (author)

  16. Development of a method for the estimation of the useful life of the target in one helical; Desarrollo de un metodo para la estimacion de la vida util del target en una unidad de tomoterapia helicoidal

    Energy Technology Data Exchange (ETDEWEB)

    Delgado Aparicio, J. M.; Garcia Repiso, S.; Martin Rincon, C.; Perez Alvarez, M. E.; Verde Velasco, J. M.; Ramos Pacho, J. A.; Saez Beltran, M.; Gomez Gonzalez, N.; Cons Perez, N.; Sena Espinel, E. de

    2013-07-01

    The objective of this study is to evaluate the effect of this degradation and develop a method for the estimation of the duration of the life of the target independently used internally by the technical service. This can serve to plan the date of intervention when it comes to replace this component. (Author)

  17. Development of a software tool for the management of quality control in a helical tomotherapy unit; Desarrollo de una herramienta de software para la gestion integral del control de calidad en una unidad de tomoterapia helicoidal

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Repiso, S.; Hernandez Rodriguez, J.; Martin Rincon, C.; Ramos Pacho, J. A.; Verde Velasco, J. M.; Delgado Aparacio, J. M.; Perez Alvarez, M. e.; Gomez Gonzalez, N.; Cons Perez, V.; Saez Beltran, M.

    2013-07-01

    The large amount of data and information that is managed in units of external radiotherapy quality control tests makes necessary the use of tools that facilitate, on the one hand, the management of measures and results in real time, and on other tasks of management, file, query and reporting of stored data. This paper presents an application of software of own development which is used for the integral management of the helical TomoTherapy unit in the aspects related to the roles and responsibilities of the hospital Radiophysics. (Author)

  18. The TMS34010 graphic processor - an architecture for image visualization in NMR tomography; O processador grafico TMS34010 - uma arquitetura para visualizacao de imagem em tomografia por RMN

    Energy Technology Data Exchange (ETDEWEB)

    Slaets, Jan Frans Willem; Paiva, Maria Stela Veludo de; Almeida, Lirio O B

    1990-12-31

    This abstract presents a description of the minimum system implemented with the graphic processor TMS34010, which will be used in the reconstruction, treatment and interpretation f images obtained by NMR tomography. The project is being developed in the LIE (Electronic Instrumentation Laboratory), of the Sao Carlos Chemistry and Physical Institute, S P, Brazil and is already in operation 4 refs., 7 figs.

  19. Development and application of a pediatric head phantom for dosimetry in computed tomography; Desenvolvimento e aplicacao de um simulador pediatrico craniano para dosimetria em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Elaine Wirney

    2016-11-01

    To determine the exposure levels and the absorbed dose in patients undergoing CT scans, is necessary to calculate the CT dose index in measurements with a PMMA or water phantom. The phantom must be enough to simulate the attenuation and scattering characteristics of a human body or parts in a radiation field. The CT specific quantities : CT air kerma index (Ca,100) , weighted CT air kerma index (CW ), a total volume CT air kerma index (Cvol) and the CT air kerma-length product (PKL) must be determined and compared to literature reference levels. In this work a head pediatric phantom was developed, considering that the Brazilian published Diagnostic Reference Levels (DRL) are based on adult phantom measurements. This developed phantom shows a construction innovation using materials to simulate the skullcap, cortical bone (aluminum) and cancellous bone (PVC), and it was filled with distilled water. The phantom dimension follows the recommendations of the World Health Organization and the International Commission on Radiation Units for children from 0 to 5 years old head size: diameter of 160 mm and height of 155 mm. The skullcap has 4 mm of thickness and 111.9 mm of internal diameter. In order to evaluate its behavior, tests were carried out in calibration laboratories and in clinical beams. The results showed attenuation up to 23% when different materials are used as skullcap, demonstrating that the DRLs adopted could be overestimating the dose received by pediatric patients. It is observed that the dose received by CT skull scans presents different distribution, due to the skullcap partially attenuation and/or backscattering which is not considered when the PMMA phantom is used.

  20. Bronchial asthma: correlation of high resolution computerized tomography findings with clinical data; Asma bronquica: correlacao de achados em tomografia computadorizada de alta resolucao com dados clinicos

    Energy Technology Data Exchange (ETDEWEB)

    Mogami, Roberto [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Servico de Radiologia; Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia; Kirk, Kennedy; Capone, Domenico [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Servico de Pneumologia; Daltro, Pedro [Instituto Fernandes Figueira, Rio de Janeiro, RJ (Brazil). Servico de Radiologia

    1999-04-01

    In this work we did a sectional study of 31 asthmatic patients with several levels of disease severity, which were submitted to high resolution computed tomography of the thorax and spirometry, between the months of July, 1995 and August, 1997. The tomographic findings were correlated with the clinical classification of the patients and the most frequent tomographic findings were bronchial wall thickening, bronchial dilatation, air trapping, centrilobular opacities, cicatricial linear shadows, mucoid impaction, emphysema and atelectasis. In asthmatic patients of long duration we observed small airway disease and irreversible lesions as the predominant findings. In smoking patients there was no high frequency of emphysema. (author)

  1. Computed tomographic study of 50 patients with hypodense hepatic injuries in childhood; Estudo de 50 casos por tomografia computadorizada de lesoes hipodensas hepaticas fundamentais na infancia

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Ines Minniti Rodrigues; Alvares, Beatriz Regina; Baracat, Jamal; Martins, Daniel Lahan [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Radiologia]. E-mail: iminniti@fcm.unicamp.br; Pereira, Ricardo Minniti Rodrigues [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas

    2006-03-15

    Objective: To describe the different tomographic findings in hypodense hepatic lesions in children and its differential diagnosis. Materials and methods: computed tomographic studies were obtained from 50 patients (age range: 0-16 years) with low-density liver lesions previously diagnosed by ultrasound. Images were made before and after administration of intravenous contrast medium. Image findings were analyzed and afterwards correlated with anatomopathological diagnosis. Results: forty-seven of 50 cases were confirmed, 30 by anatomopathological diagnosis. Most of then were benign lesions, hemangioma in 20%. Such lesions presented a homogeneous contrast absorption, mainly at the delayed phase, differing from malignant lesions. Metastasis was the most frequently found malignant lesion (18%). Conclusion: computed tomographic study is of great value in complementing the diagnosis of hypodense hepatic lesions in children, and must follow ultrasound diagnosis as a routine procedure. (author)

  2. 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

    Energy Technology Data Exchange (ETDEWEB)

    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)

  3. Density evaluation by computerized tomography in plain soils over different manipulation systems; Avaliacao da densidade pelo metodo da tomografia computadorizada de um planossolo sob diferentes sistemas de manejo

    Energy Technology Data Exchange (ETDEWEB)

    Pedrotti, Alceu [Lavras Univ., MG (Brazil). Dept. de Ciencia do Solo; Pauletto, Eloy Antonio [Pelotas Univ., RS (Brazil). Dept. de Solos; Crestana, Silvio [Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA), Sao Carlos, SP (Brazil). Centro Nacional de Pesquisa e Desenvolvimento de Instrumentacao Agropecuaria (CNPDIA)

    1996-08-01

    The objective of this paper is the evaluation of a plain soil density in different culture systems determined by X ray computerized tomography.It was observed a larger variation in densities in soils profiles analysed. The identification of layers is better utilising computerized tomography than others technic 1 fig.

  4. Pancreatite necro-hemorrágica: utilização da tomografia computadorizada como método diagnóstico auxiliar

    Directory of Open Access Journals (Sweden)

    Pedro Jorge Furtado Freitas

    2015-09-01

    Full Text Available O presente trabalho relata um caso de uma das formas mais graves de pancreatite aguda, a pancreatite necro- hemorrágica. Nessa condição, o paciente fica em uma linha tênue entre uma boa evolução e a queda do estado geral, com alta mortalidade. O paciente deu entrada no hospital com fortes dores em abdome superior. No exame tomográfico constatou-se pancreatite com sinais sugestivos de necrose, sendo tratado clinicamente por sete dias. Após manutenção radiológica do quadro, o paciente foi submetido a uma laparotomia exploradora com necrosectomia e colocação de dreno. Paciente evoluiu bem clinicamente, tendo alta hospitalar no 17º dia de internação.

  5. Computerized tomography in normal abdomen: retrospective study of renal hila angles; Tomografia computadorizada de abdome normal: estudo retrospectivo das angulacoes dos hilos renais

    Energy Technology Data Exchange (ETDEWEB)

    Sakate, Makoto; Sakate, Alzira Teruio Yida; Yamashita, Seizo; Teixeira, Altamir dos Santos; Correia, Luis Antonio [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Faculdade de Medicina]. E-mail: msakate@fmb.unesp.br; Barbosa, Luciano [Universidade Estadual Paulista (UNESP), Botucatu, SP (Brazil). Inst. de Biociencias

    2009-01-15

    To obtain mean angulation values for renal hila in relation to the horizontal plane traced over the right and left spinal erector muscles, considering the center of the lumbar vertebral spine as a parameter for measuring the renal hila angles. The authors have analyzed 250 abdominal computed tomography studies of both male and female healthy individuals (128 men with mean age 52.45 {+-} 17.42 years, and 122 women with mean age 54.39 {+-} 18.27 years), corresponding to 500 renal hila evaluated. The mean angulation of each hilum in relation to the horizontal plane was obtained taking acute angles into consideration. The comparative study have not found any statistically significant difference in acute angles of renal hila between male and female individuals. The statistical analysis demonstrated limits of 40.40 deg and 44.54 deg for mean right hilum angulation and 39.91 deg and 43.23 deg for mean left hilum angulation, with a confidence interval of 95% . Renal hila present similar angulation independently of sex. Higher angulation values correspond to hyper-rotation or excessive rotation, and lower angulation values, to incomplete or reverse rotation. (author)

  6. Computed tomography-guided percutaneous biopsy of pancreatic masses using pneumodissection; Biopsia percutanea de massas pancreaticas guiada por tomografia computadorizada com pneumodisseccao

    Energy Technology Data Exchange (ETDEWEB)

    Tyng, Chiang Jeng; Bitencourt, Almir Galvao Vieira; Almeida, Maria Fernanda Arruda; Barbosa, Paula Nicole Vieira; Martins, Eduardo Bruno Lobato; Junior, Joao Paulo Kawaoka Matushita; Chojniak, Rubens, E-mail: chiangjengtyng@gmail.com [Hospital A.C. Camargo, Sao Paulo, SP (Brazil). Dept. de Imagem; Coimbra, Felipe Jose Fernandez [Hospital A.C. Camargo, Sao Paulo, SP (Brazil). Dept. de Cirurgia Abdominal

    2013-05-15

    Objective: to describe the technique of computed tomography-guided percutaneous biopsy of pancreatic tumors with pneumodissection. Materials and methods: in the period from June 2011 to May 2012, seven computed tomography guided percutaneous biopsies of pancreatic tumors utilizing pneumodissection were performed in the authors' institution. All the procedures were performed with an automatic biopsy gun and coaxial system with Tru-core needles. The biopsy specimens were histologically assessed. Results: in all the cases the pancreatic mass could not be directly approached by computed tomography without passing through major organs and structures. The injection of air allowed the displacement of adjacent structures and creation of a safe coaxial needle pathway toward the lesion. Biopsy was successfully performed in all the cases, yielding appropriate specimens for pathological analysis. Conclusion: Pneumodissection is a safe, inexpensive and technically easy approach to perform percutaneous biopsy in selected cases where direct access to the pancreatic tumor is not feasible. (author)

  7. Squamous cell carcinoma of the external auditory canal: computed tomography findings in six cases; Carcinoma espinocelular do conduto auditivo externo: estudo por tomografia computadorizada de seis casos

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Fabio Mota; Paes Junior, Ademar Jose de Oliveira; Tornin, Olger de Souza [Complexo Hospitalar Heliopolis, Sao Paulo, SP (Brazil). Servico de Diagnostico por Imagem]. E-mail: fmg961@yahoo.com.br; Souza, Ricardo Pires de [Complexo Hospitalar Heliopolis, Sao Paulo, SP (Brazil). Programa de Residencia Medica em Radiologia e Diagnostico por Imagem

    2005-05-15

    Objective: to evaluate the role of computed tomography in the assessment of deep extension of squamous cell carcinoma of the external auditory canal. Materials and methods: in the period between May 1995 and December 2003 six patients with squamous cell carcinoma of the external auditory canal were submitted to computed tomography scan at 'Hospital Heliopolis', Sao Paulo, SP, Brazil, including axial and coronal slices with soft tissue and bone algorithms. Results: thickening of the soft tissue of the external auditory canal was seen in all patients, bone erosion and invasion of the middle ear in five (83.3%), invasion of the mastoid and parotid gland in four (66.7%), invasion of the temporomandibular joint in three (50%), and invasion of the middle cranial fossa, carotid canal and cervical lymph node enlargement in two (33.3%) patients. Conclusion: assessment of deep extension of squamous cell carcinoma of the external auditory canal using computed tomography is useful for clinical staging of the disease allowing better therapeutic planning for these patients. (author)

  8. Abdominal adipose tissue distribution in obese children. US versus CT measurements; Valutazione della distribuzione del tessuto adiposo addominale nei bambini obesi. Confronto tra ecografia e Tomografia Computerizzata

    Energy Technology Data Exchange (ETDEWEB)

    Ferrozzi, F.; Zuccoli, G.; Tognini, G.; Castriota-Scanderbeg, A.; Bacchini, E. [Parma Univ., Parma (Italy). Ist. di Scienze Radiologiche; Bernasconi, S. [Modena Univ., Modena (Italy). Clinica Pediatrica; Campani, R. [Pavia Univ., Pavia (Italy). Ist. di Radiologia

    1999-12-01

    Computed Tomography (CT) and, more recently, ultrasound (US), have proved excellent tools for quantifying adipose tissue distribution. Body fat distribution is an important factor in the treatment of obesity and its complications. In this work it is investigated the correlation between CT and US measurements in pediatric obesity. Forty obese children and adolescents aged 4.1-14.8 years were submitted to CT and US. Intra-abdominal, subcutaneous and total body fat were calculated (in cm{sup 2}), with the CT image analysis software. The rectus muscle-spine and rectus muscle-aorta distances, as indicative of visceral fat thickness, were measured on US images with(out) compression. The distance between skin fat and fat-rectus muscle interfaces was measured as subcutaneous fat thickness. US-CT findings have been compared with other morphometric variables-i.e., patient's (ideal) body weight and skin fold measures. A statistically significant correlation was found between the CT measurement of visceral fat and the aorta-rectus muscle and rectus muscle-spine distances (r=0.80 and 0.74, respectively). The US measurements of subcutaneous fat were correlated with CT subcutaneous fat area (r=0.82). No correlation was found between overweight, as calculated by body mass index, and CT or US fat. In conclusions, the findings indicate that US is as useful as CT in evaluating body fat distribution in pediatric obesity. [Italian] La TC e piu' recentemente l'ecografia si sono dimostrate eccellenti tecniche di valutazione della quantita' e della distribuzione del tessuto adiposo corporeo. La compartimentazione del grasso corporeo ha, infatti, importanti implicazioni per il trattamento dell'obesita' e delle sue complicanze. Scopo dello studio e' stato quello di correlare i risultati ottenuti con la TC con quelli ecografici nella valutazione dell'obesita' del paziente pediatrico. Quaranta bambini obesi con eta' compresa tra 4,1 e 14,8 anni sono stati valutati sia con TC che con ecografia. E' stato determinato il valore assoluto del grasso intra-addominale, sottocutaneo e totale, espresso in cm{sup 2,} sulla base delle elaborazioni TC. Con l'ecografia sono state valutate le distanze tra il muscolo retto e la colonna vertebrale e tra il muscolo retto e l'aorta, senza e con compressione dosata, quali parametri indicativi dello spessore del grasso viscerale nonche' la distanza tra cute e muscolo retto quale indicatore del grasso sottocutaneo. I risultati dell'ecografia e della TC sono stati inoltre correlati con altre variabili morfometriche (peso, peso corporeo ideale, plicometria cutanea). E' stata dimostrata correlazione statisticamente significativa tra la quota di grasso viscerale misurato con la TC e le distanze muscolo retto/aorta (r=0,80) e muscolo retto/colonna vertebrale (r=0,74). Anche l'area sottocutanea misurata con la TC si correlava (r=0,82) con la distanza cute/muscolo retto valutata ecograficamente. Non e' stata riscontrata alcuna correlazione tra l'indice di massa corporea e i dati ecografici e TC. I risultati ottenuti suggeriscono che l'ecografia puo' essere utilizzata in alternativa alla TC nella valutazione della distribuzione del grasso corporeo nei bambini obesi.

  9. The TMS34010 graphic processor - an architecture for image visualization in NMR tomography; O processador grafico TMS34010 - uma arquitetura para visualizacao de imagem em tomografia por RMN

    Energy Technology Data Exchange (ETDEWEB)

    Slaets, Jan Frans Willem; Paiva, Maria Stela Veludo de; Almeida, Lirio O.B

    1989-12-31

    This abstract presents a description of the minimum system implemented with the graphic processor TMS34010, which will be used in the reconstruction, treatment and interpretation f images obtained by NMR tomography. The project is being developed in the LIE (Electronic Instrumentation Laboratory), of the Sao Carlos Chemistry and Physical Institute, S P, Brazil and is already in operation 4 refs., 7 figs.

  10. Monte Carlo determination of dose in crystalline and thyroid during chest tomography examinations; Determinacion Monte Carlo de dosis en cristalino y tiroides durante examenes de tomografia de torax

    Energy Technology Data Exchange (ETDEWEB)

    Quispe H, B.; Pena V, J. D.; Waldo B, G.; Leon M, M.; Ceron R, P.; Vallejo H, A.; Sosa A, M. [Universidad de Guanajuato, Campus Leon, Division de Ciencias e Ingenierias, Loma del Bosque 103, Lomas del Campestre, 37150 Leon, Guanajuato (Mexico); Vega C, H. R., E-mail: b.quispehuillcara@ugto.mx [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas, Zac. (Mexico)

    2017-10-15

    Computed tomography is a diagnostic imaging method that deposits higher doses than other radio diagnosis methods. The knowledge of the spectrum of X-rays is important, since is in direct function with the dose absorbed by the patient. In this work we estimated the spectrum of X-rays, produced during the interaction of monoenergetic electrons of 130 KeV with Tungsten white, in order to determine their energetic characteristics at 50 cm from the focal point. The study was done using Monte Carlo methods with the code MCNP5 where the X-ray tube of a Siemens SOMATOM Perspective tomograph of the General Regional Hospital of Leon, Mexico was modeled. In the calculations, 3 x 10{sup 8} stories were used and a relative uncertainty of less than 0.1% was obtained. Also, a neck manikin with thyroid, thorax and head that included the eye, the table and gantry with 70 cm opening of the tomography was modeled. The X-ray spectrum calculated with a cut thickness of 10 mm limited by Pb collimators was used as the source term. The radiological service routine scanning protocol was used for chest computed tomography; the step-by-step or instant trigger method was simulated by moving the manikin coordinates for each cut and 360 degree continuous rotation movement. 36 positions of the X-ray tube were used in steps of 10 degrees. The radiation dispersed in the thorax deposits a dose of 2.063 mGy in crystalline and 252 mGy in thyroid. (Author)

  11. Dose optimization in adult patients exams in a computerized tomography service; Otimizacao de dose em exames de pacientes adultos em um servico de tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Pimentel, Juliana; Finatto, Jerusa D.; Silva, Ana Maria Marques da, E-mail: ana.marques@pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS), Porto Alegre, RS (Brazil); Froner, Ana Paula P. [CDI Tomografia e Ressonancia Magnetica, Porto Alegre, RS (Brazil)

    2013-08-15

    This paper presents a study of dose optimization in computed tomography X-ray of skull, chest and abdomen of adult patients, performed in a diagnostic imaging service in a large hospital. Images of a simulated dose phantom were acquired and the kVp, mAs, pitch, thickness and CTDI{sub vol} were collected directly from the equipment. Using the PACS system, regions of interest were delineated, where the mean and standard deviation of CT numbers for each protocol were been calculated. The optimization took into account the maintenance of the CT number and noise from images acquired with clinical protocols. It was observed that the protocols used in the service, in general, exhibit a low dose, despite the great variability among the different professional shifts. In examinations of the chest, skull and abdomen, changes in the values of mAs and pitch were suggested, allowing dose reductions (60%, 17% and 19%, respectively), without compromising the image diagnostic quality. (author)

  12. Evaluation of uniformity and noise consistency test in computerized tomography; Avaliacao do teste de constancia de uniformidade e ruido em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Garrafiel, Fabricio N.; Lykawka, Rochelle; Bacelar, Alexandre; Anes, Mauricio [Hospital de Clinicas de Porto Alegre (HCPA), Porto Alegre, RS (Brazil); Alva-Sanchez, Mirko S.; Pianoschi, Thatiane [Universidade Federal de Ciencias da Saude de Porto Alegre (UFCSPA), Porto Alegre, RS (Brazil)

    2016-07-01

    The quality control in computed tomography (CT) includes constancy tests concerning CT number measured in a water tank and its response as uniformity, noise and accuracy. Differences to It's performance limits and frequency established by the national legislation and the manufacturers are well known. The objective of this study was to evaluate these tests proceeding the periodicity of national legislation. The tests were conducted over a three equipment of different manufacturers. Each equipment has acquisition parameters and specific phantoms. The equipment presented adequate performance and consistency when compared their results to the limits determined by manufacturers and national legislation. Thus, it is important to evaluate these differences and tailor the testing protocols to meet the established quality requirements. (author)

  13. Measurement and analyses of spectral noise power in computed tomography; Medida y analisis del espectro de potencias del ruido en imagenes de tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Castro Tejero, P.; Garayoa Roca, J.

    2014-07-01

    Noise is an important feature of image quality. The standard deviation of pixel value in a uniform region has been frequently used as a metric to characterize noise. However, this measure does not provide any information about the noise spatial distribution. A more complete description is given by the Noise Power Spectrum (NPS) which provides both the amount and the spatial correlation of noise. The objective of the present work is to present a methodology and a computing tool to obtain the NPS, in order to analyze its components and study their behaviour for computed tomography (TC) images. Our results show that the major contribution to NPS is a random source for all the explored working conditions. The structural component is constrained to the low frequency region, where it can be as important as the random component. Moreover, we observe that the reconstruction filter and the acquisition technique, axial or helical, have a clear impact on the image noise. (Author)

  14. Cone beam computed tomography in veterinary dentistry: description and standardization of the technique; Tomografia computadorizada de feixe conico na odontologia veterinaria: descricao e padronizacao da tecnica

    Energy Technology Data Exchange (ETDEWEB)

    Roza, Marcello R. [Universidade Federal de Goias (UFG), Goianai, GO (Brazil)], e-mail: marcelloroza@gmail.com; Silva, Luiz A.F.; Fioravanti, Maria C. S. [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Escola de Veterinaria. Dept. de Medicina Veterinaria; Januario, Alessandro L. [International Team for Implantology (ITI), Sao Paulo, SP (Brazil); Barriviera, Mauricio [Universidade Catolica de Brasilia (UCB), DF (Brazil). Faculdade de Odontologia. Dept. de Radiologia; Oliveira, Alexandre C.A. [Faculdade de Odontologia Sao Leopoldo Mandic, Campinas, SP (Brazil)

    2009-08-15

    Eleven dogs and four cats with buccodental alterations, treated in the Centro Veterinario do Gama, in Brasilia, DF, Brazil, were submitted to cone beam computed tomography. The exams were carried out in a i-CAT tomograph, using for image acquisition six centimeters height, 40 seconds time, 0.2 voxel, 120 kilovolts and 46.72 milli amperes per second. The ideal positioning of the animal for the exam was also determined in this study and it proved to be fundamental for successful examination, which required a simple and safe anesthetic protocol due to the relatively short period of time necessary to obtain the images. Several alterations and diseases were identified with accurate imaging, demonstrating that cone beam computed tomography is a safe, accessible and feasible imaging method which could be included in the small animal dentistry routine diagnosis. (author)

  15. Computed tomography findings in patients less than 20 years old with lymphoma; Aspectos da tomografia computadorizada no linfoma em pacientes abaixo de 20 anos de idade

    Energy Technology Data Exchange (ETDEWEB)

    Borba, Adriana Moreira Viana [Pontificia Universidade Catolica do Rio de Janeiro (PUC-RJ), Rio de Janeiro, RJ (Brazil). Escola de Medicina; Monteiro, Alexandra Maria Vieira; Lucena, Stella Beatriz Goncalves de [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Faculdade de Ciencias Medicas; Lima, Claudio Marcio Amaral de Oliveira; Ribeiro, Erica Barreiros [Hospital Naval Marcilio Dias, Rio de Janeiro, RJ (Brazil)]. E-mail: cmaol@br.inter.net; Skinner, Luis Flavio [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Faculdade de Ciencias Medicas. Hospital Universitario Pedro Ernesto (HUPE)

    2007-03-15

    Objective: To describe the general findings of lymphoma and their histological patterns in patients less than 20 years old. Materials And Methods: Twenty-two cases (16 male and 6 female, mean age 11.5 years) from the digital archive of computed tomography at the Cancer Control Center of Hospital Universitario Pedro Ernesto - Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil, were retrospectively analyzed in the period between March 2003 and July 2005. Of these 22 cases, 12 were Hodgkin's and 10 were non-Hodgkin's. Results: Overall, mediastinal lymphadenomegaly was the most frequent finding (59%), with predominance in the Hodgkin's subgroup (75%), followed by hepatosplenomegaly (50%) and cervical and retroperitoneal lymphadenomegaly (27.3%). The Hodgkin's subgroup presented a prevalence of lymphadenopathy, in many lymph node chains, followed by hepatosplenomegaly (50%). One case was found with unilateral tonsillar mass, pulmonary ground-glass opacities, and renal nodules. In the non-Hodgkin's subgroup, the disease was predominantly extranodal, characterized by hepatosplenomegaly (50%), thickening of the intestinal wall (40%), pleural effusion (30%), pulmonary nodule (20%), ascites (10%), pericardial effusion (10%) and mixed bone lesions (10%). Conclusion: Computed tomography is an extremely useful method for detection, staging and follow-up of lymphomas, with alert findings like mediastinal lymphadenopathy, hepatosplenomegaly, unilateral tonsillar mass and thickening of intestinal wall. (author)

  16. Rectal contrast-enhanced computed tomography in the diagnosis of acute appendicitis; Tomografia computarizada con contraste rectal en el diagnostico de la apendicitis aguda

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    To assess the efficacy and utility of computed tomography (CT) in the diagnosis of appendicitis, and to evaluate the reliability of CT findings in right iliac fossa in the confirmation or exclusion of this diagnosis. Over a one-year period, 152 patients presenting clinical signs of appendicitis underwent CT scans. The images were reviewed by two radiologists who considered whether the appendix was normal or enlarged and the existence of other signs of appendicitis for the purpose of determining whether or not the patient presented appendicitis. The definitive diagnoses were established by surgery or by clinical follow-up. The sensitivity of CT for the diagnosis of appendicitis was 81.8%, the specificity was 95.3%, the positive predictive value was 93.1%, the negative predictive value was 87.2% and the reliability was 89.9%. The signs of appendicitis observed were: appendicoliths (sensitivity 30.3% and specificity 98.8%), fluid collections (sensitivity 19.7%, specificity 96.5%), cecal enlargement (sensitivity 21.2%, specificity 97.7%), inflammation of pericecal fat (sensitivity 72.7%, specificity 90.7%), fascial thickening (sensitivity 48.5%, specificity 91.9%) and an appendix measuring more than 6 mm (sensitivity 78.8%, specificity 94.3%). Adenopathy and free peritoneal fluid were not significantly related to appendicitis. The presence of a normal appendix filled with air or contrast material had an elevated negative predictive value with respect to appendicitis. In 35 of the 94 cases with negative CT scans, the images suggested alternative diagnoses. CT is a highly reliable diagnostic method for appendicitis. The observation of an appendix filled with air or contrast material has an elevated negative predictive value. The presence of appendicoliths has an elevated positive predictive value. (Author) 29 refs.

  17. Comparison of ultrasonography and computed tomography in the diagnosis of acute appendicitis; Comparacion de la ecografia y la tomografia computarizada en el diagnostico de la apendicitis aguda

    Energy Technology Data Exchange (ETDEWEB)

    Cura, J. L. del; Oleaga, L.; Grande, D.; Farina, M. A.; Isusi, M. [Hospital de Basurto. Bilbao (Spain)

    2001-07-01

    The compare the efficacy of ultrasonography and computed tomography (CT) in cases of suspected appendicitis. To study to what extent age, sex and habits of the patients, as well as the clinical context, influence the diagnostic yield of these two technique. Over a one-year period, 152 patients underwent ultrasonography and CT because of the clinical suspicion of appendicitis. The studies were carried out independently, and the results of each in terms of the presence or absence of appendicitis were unknown to the specialists performing the other. The final diagnoses were established by surgical treatment or clinical follow-up. The sensitivity of CT for the diagnosis of appendicitis was 82%, the specificity was 95%, the positive predictive value was 93%, the negative predictive value was 87% and the reliability was 90%. Ultrasonography has a sensitivity of 83%, a specificity of 97%, a positive predictive value of 95%, a negative predictive value of 88% and a reliability of 91%. Ultrasound was more efficient in patients in which there was a high clinical suspicion and in children, while the results with CT were better in patients in which the clinical diagnosis was less clear. The incidence of false negatives and positives was higher with ultrasound, while CT was more frequently able to identify a normal appendix. Sex and habits had no influence on the respective efficacies, although the performance of ultrasound was simplified in thin patients and that of CT in obese individuals. Ultrasonography and CT are highly reliable in cases of suspected appendicitis, especially when this diagnosis is conformed. Ultrasound is recommended as the technique of choice in children and in patients in which the clinical suspicion is strong. The yield of CT is somewhat greater when the clinical signs and symptoms are less clear. However, the efficacy of both techniques ultimately depends on the expertise of the specialist who interprets them. (Author) 62 refs.

  18. Paracoccidioidomycosis: high-resolution computed tomography - anatomo-pathological correlation; Paracoccidioidomicose: correlacao da tomografia computadorizada de alta resolucao com a anatomopatologia

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson; Muniz, Maria Angelica Soares; Santos, Maria Lucia de Oliveira [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Radiologia; Moraes, Heleno Pinto de [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Patologia; Capone, Domenico [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Pneumologia

    2000-12-01

    We reviewed the high-resolution computed tomography scans of 13 patients with paracoccidioidomycosis and correlated the findings with the anatomo-pathological findings of 5 patients. The most frequent findings observed were thickening of the interlobular septa, emphysema, ground glass areas, thickening of bronchial walls, tracheal dilatation, nodules, cavities and evidence of fibrosing disease such as architectural distortion, parenchymatous bands, spicular pleural thickening, intralobular reticulate and thickening with distortion off the axial interstitium. (author)

  19. Prognosis of the computerized tomography in the severe head injury. Valor pronostico de la tomografia axial computada (TC) en los traumatismos craneoencefalicos severos

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    Garcia-Nieto, J.J.; Lorenzo Dominguez, M.T.; Martin Sanchez, M.J.; Sanchez Gonzalez, E.

    1991-01-01

    A prospective study is made with sixty five people affected of severe head injury, that is to say, with eight or less points in the Glasgow Coma Scale (GCS), when they get to the hospital. They are studied by computerized tomography at admission, and three and seven days after arrival. In this way, we appraise the type of the lesion, its intensity and the possible prognosis, considering in the last case three features: a) ventricular collapse; b) the mean line structure s shift; and c) effects on perimesencephalic cistern. The findings were parametized and we were able to introduce into the computer program relationships between these findings and the end results. These last ones were appraised through the Glasgow Outcome Scale (GOS). We could show that certain findings in computerized tomography scans have an unavoidable prognosis while as others have a more favorable prognosis. (Author)

  20. Typical and atypical presentations of paranasal sinus mucocele at computed tomography; Apresentacoes tipicas de mucocele dos seios paranasais na tomografia computadorizada

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    Carvalho, Bruna Vilaca de; Lopes, Izabella de Campos Carvalho; Correa, James de Brito, E-mail: brunavilaca@gmail.com [Hospital Mater Dei, Belo Horizonte, MG (Brazil). Dept. de Radiologia e Diagnostico por Imagem; Ramos, Laura Filgueiras Mourao; Motta, Emilia Guerra Pinto Coelho; Diniz, Renata Lopes Furletti Caldeira [Hospital Mater Dei, Belo Horizonte, MG (Brazil)

    2013-11-15

    Mucoceles are cystic masses that generally affect the sinuses. It occurs as a result from obstruction of the ostium of a sinus and consequential accumulation of mucus. Frontal and ethmoid sinuses are mostly affected. Usually, the clinical symptoms are insidious, varying with the extent of the affected region. The treatment is surgical and endoscopic surgery is the method of choice in most cases. The present study is aimed at describing the main characteristics of paranasal sinuses mucoceles, demonstrating and illustrating a series of atypical presentations with emphasis on imaging findings. (author)

  1. Development of Image Reconstruction Algorithms in electrical Capacitance Tomography; Desarrollo de algoritmos de reconstruccion de imagenes en tomografia de capacitancia electrica

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    Fernandez Marron, J. L.; Alberdi Primicia, J.; Barcala Riveira, J. M.

    2007-12-28

    The Electrical Capacitance Tomography (ECT) has not obtained a good development in order to be used at industrial level. That is due first to difficulties in the measurement of very little capacitances (in the range of femto farads) and second to the problem of reconstruction on- line of the images. This problem is due also to the small numbers of electrodes (maximum 16), that made the usual algorithms of reconstruction has many errors. In this work it is described a new purely geometrical method that could be used for this purpose. (Author) 4 refs.

  2. CT imaging in the surgical treatment of one-sided extraarticular temporomandibular joint ankylosis; Uso da tomografia computadorizada no planejamento cirurgico da anquilose temporomandibular extra-articular unilateral

    Energy Technology Data Exchange (ETDEWEB)

    Villamizar, Lenin A.; Ghirelli, Carolina de Oliveira; Baroni, Carina Outi; Ferro, Daniel; Pinto, Ana Carolina Brandao de Campos Fonseca, E-mail: carinaouti@yahoo.com.br [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia. Dept. de Cirurgia

    2012-07-01

    Temporomandibular joint (TMJ) ankylosis is characterized by difficulty to open the mouth. The ankylosis may be articular when TJM is involved and extra-articular when other factors lead to a restriction of chewing movements without TJM involvement. Case report of one patient with unilateral ankylosis and his surgical planning through the tomography imaging. CT imaging helps preoperative planning because it can locate the exact point of injury and can make the difference between the true and false ankylosis of the TJM. (author)

  3. Radiographic and tomographic study of the elbow joint in dogs; Avaliacao morfologica e morfometrica da articulacao umerorradioulnar em caes atraves de exames radiograficos e por tomografia computadorizada

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    Sendyk-Grunkraut, Alessandra; Martin, Claudia M.; Souza, Alexandre N.A.; Patricio, Geni Cristina F.; Lorigados, Carla A.B.; Matera, Julia M.; Fonseca-Pinto, Ana C.B.C., E-mail: anacarol@usp.br [Universidade de Sao Paulo (FMVZ/USP), SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia

    2017-02-15

    Elbow dysplasia disease includes an united anconeal process, fragmented medial coronoid process, osteochondrosis of humeral trochlea, articular incongruity and degenerative joint disease. The aim of this study was to present detailed morphologic and morphometric aspects of the elbow joint in dog in clinical and correlate with radiographic and tomographic (CT) exam. Inter-observer variation for articular incongruity measurements by CT, comparative analysis in the radiographic exam, angle in ulnar notch and its comparative analysis between radiographic and tomographic agreement examination in 44 elbow of dogs with different ages were evaluated. The statistics analyses included the kappa coefficient and interclass correlation and Fischer's test and McNemar's test. It was evidenced that individual performance of each radiographic incidence had poor agreement with the tomographic exam, suggesting that the accomplishment of more than two radiograph views are needed. There was no agreement between the three evaluators in the ulnar notch angle at radiographic and tomographic exams. However, there was good/moderate agreement for articular incongruity measurement in the sagittal plane between evaluators. It was possible to conclude that none of the five radiographic incidences was better than the others for radiographic analysis because each incidence had a better identification of a particular elbow compartment; measurements at the tomographic exam to evaluate radioulnar incongruity had no reproductiveness in the frontal plane, but in sagittal plan had a good/moderate agreement between observers and the angle in ulnar notch presented no repeatability at radiographic exam and no reproductiveness at tomographic exam. (author)

  4. Interstitial pulmonary alterations in visceral leishmaniasis: evaluation with high-resolution computed tomography; Alteracoes pulmonares intersticiais na leishmaniose visceral: avaliacao pela tomografia computadorizada de alta resolucao

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Norma Selma Santos; Cerri, Giovanni Guido [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina. Dept. de Radiologia

    1999-08-01

    Visceral leishmaniasis, also called kala-azar, is a disease caused by a protozoan, the Leishmania donovani chagasi, that comprises reticuloendothelial system with involvement of the liver, spleen and bone marrow. It is endemic in some areas of northeastern Brazil and other countries of Latin America and Africa. The pathogenesis is related to the immunologic system of patients that present with the inability to activate the phagocytosis of the macrophages. As occurs in the liver and kidneys, the lungs are also involved with interstitial abnormalities caused by Leishmania that are not dependent upon the presence of the parasite. The histopathologic changes described are the involvement of inter alveolar septal in three different phases, irregularly and diffusely throughout the whole pulmonary parenchyma. This work analyzed high-resolution computed tomography (HRCT) of the thorax in 17 patients with visceral leishmaniasis in order to detect and characterize the abnormalities described in the anatomo pathologic findings reported in the literature. The HRCT is being used to evaluate chronic interstitial lung disease in a good correlation with histologic findings. The most common findings detected by HRCT were the reticular opacities that include peribronchovascular interstitial thickening and interlobular septal thickening an ground-glass opacity. The HRCT suggests that similar changes to that found in alveolar structures may occur in the secondary pulmonary lobule and that the involvement in the parenchymal interstitium represents the findings reported by pathological studies in visceral leishmaniasis. (author)

  5. Computed tomography of the adrenals in patients with tuberculosis; Emprego da tomografia computadorizada na deteccao de alteracoes das adrenais em doentes com tuberculose

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    Yamashita, Seizo; Machado, Jussara Marcondes; Morceli, Jose [UNESP, Botucatu, SP (Brazil). Faculdade de Medicina. Dept. de Doencas Tropicais e Diagnostico por Imagem]. E-mail: seizo_eid@uol.com.br

    2004-06-01

    We evaluated the adrenals of individuals without tuberculosis (group 1 - G1) and with tuberculosis (group 2 - G2) using computed tomography. The antero-posterior length, the thickness, and the longitudinal length of the adrenals were compared in G1 and G2. The duration of the disease, the occurrence of morphologic abnormalities in G2, the distribution according to sex, age and skin color were also studied. There was difference in the antero-posterior length and thickness of right adrenal between G1 and G2. A higher prevalence of white skin male individuals was observed in G2. There was no association between duration of the disease and the occurrence of morphologic abnormalities in G2. A higher occurrence of adrenal enlargement was observed in G2. The main computed tomography findings in patients with tuberculosis were enlargement of the adrenal without calcification, enlargement of the adrenal with punctiform calcifications, and residual calcification of the adrenal. (author)

  6. Dose estimation in CT exams of the abdomen based on values of DLP; Estimativa da dose em exames de tomografia de abdome com base nos valores de DLP

    Energy Technology Data Exchange (ETDEWEB)

    Kikuti, C.F.; Medeiros, R.B.; Salvadori, P.S.; Costa, D.M.C; D' lppolito, G., E-mail: kikuticf@gmail.com, E-mail: rbitelli2011@gmail.com [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Coordenadoria de Fisica e Higiene das Radiacoes. Departamento de Diagnostico por Imagem

    2013-10-01

    One of the challenges of multidetector computerized tomography is to minimize the risk of ionizing radiation using optimized protocols since higher doses are necessary to obtain high image quality. It was also noted that, due to the geometry in image acquisition using MDCT becomes necessary to estimate dose values consistent with the hypothesis clinically and with the specificities of the tomographic equipment. The aim of this study was to estimate the doses in abdomen exams from the data recorded on the MDCT console and dimensions obtained from DICOM images of patients undergoing different clinical protocols. Were collected, from the image DICOM of 101 exams, values of the dose length product (DLP) provided by Philips Health Care - Brilliance 64 equipment console, in order to relate them with the dose values obtained by means of thermoluminescent dosimeters ( TLD ) of CasSo{sub 4}:Mn placed on the surface of a cylindrical simulator abdomen acrylic manufactured under the technical - operational conditions for a typical abdomen exam. From the data obtained, it was possible to find a factor of 1.16 ( 5 % ) indicating that the DLP values Brilliance 64 console underestimate the doses and this should be used with correction factor to estimate the total dose of the patient. (author)

  7. Measurement and analysis of noise power spectrum of computerized tomography in images; Medida y analysis del espectro de potencias del ruido en imagenes de tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Castro Tejero, P.; Garayoa Roca, J.

    2013-07-01

    This paper examines the implementation of the spectrum of powers of the noise, NPS, as metric to characterize the noise, both in magnitude and in texture, for CT scans. The NPS found show that you for convolution filters that assume a greater softening in the reconstructed image, spectrum is concentrated in the low frequencies, while for filters sharp, the spectrum extends to high frequencies. In the analyzed cases, there is a low frequency component, largely due to the structure-borne noise, which can be a potential negative effect on the detectability of injuries. (Author)

  8. Anatomic variants of interest in endoscopic sinus surgery: role of computed tomography; Variantes anatomicas de interes en cirugia endoscopica nasosinusal. Papel de la tomografia computerizada

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, S.; Arenas, J.; Fernandez, F.; Gil, S.; Guirau, M. D. [Hospital General Universitario de Alicante (Spain)

    2000-07-01

    The detailed radiological study of the anatomy of the nasal cavities and paranasal sinus is essential prior to endoscopic sinus surgery since, on the one hand, it discloses the extent of the disease and, on the other hand, it aids in the detection of the numerous anatomic variants, some of which are of great interest to the endoscopic as the lack of preoperative knowledge of them may increase the risk of complications. the objective of the present report is to review these variants, stressing those that may be associated with a greater surgical risk. Although coronal computed tomography is the technique of choice for pre endoscopy examination, certain structures and anatomic variants are better viewed in axial images. These exceptions include anterior and posterior walls of the frontal sinuses, the anatomic relationships between posterior ethmoid complex and the sphenoid sinus, the relationships between the sphenoid sinus and the optic nerve, and the detection of Onodi cells. Thus, we recommend that the radiological examination include both coronal and axial images. (Author) 16 refs.

  9. Multiphasic helical Computed Tomography of hepatocellular carcinoma. Evaluation after various percutaneous ablation procedures; Tomografia Computerizzata spirale multifasica dell'epatocarcinoma. Valutazione dopo differenti procedure ablative percutanee

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    Catalano, O.; Esposito, M.; Lobianco, R.; Cusati, B.; Altei, F.; Siani, A. [Ospedale S. Maria delle Grazie, Pozzuoli, NA (Italy). Servizio di Radiologia

    1999-12-01

    The purpose of this paper is to report the personal experience with helical CT evaluation of hepatocellular carcinoma treated with various percutaneous interventional procedures. From December 1996 to September 1998 it were examined with helical CT 41 patients (73 nodules in all) with hepatocellular carcinoma treated with percutaneous ablation therapies: conventional ethanol injection in 18 subjects (31 nodules), one-shot ethanol injection 3 (8 nodules), radiofrequency thermal ablation in 16 (25 nodules), and combined chemo embolization and ethanol injection in 4 (9 nodules). CT performed was 4-27 days after the last session, acquiring biphasic volumetric images in 14 patients and triphasic volumetric images in 27. A second treatment with subsequent CT study was performed for 28 lesions; 15 underwent 3 serial studies and 6 underwent 4 studies. Compared with pretreatment findings, the diameter was unchanged in 62% of the nodules and increased in 38%. Morphology was unchanged in 63% of the lesions while in 37% a mild deformation toward the needle path or a more regular and round shape was evident. Borders were unchanged in 37% of the cases and modified in 63%, appearing well-defined in 73% and ill-defined in 27%. The necrotic portion had a low attenuation with a nodule-to-parenchyma gradient more evident on delayed than on venous and finally arterial acquisitions; 8% of the lesions were not recognizable on unenhanced scans. During the arterial phase the residual tumor appeared hyperdense in 97% of the nodules and isodense in 3%, while during the portal phase it was hyperdense in 22%, isodense in 28% and hypodense in 50%, and during the delayed phase hypodense in 100%. Residual viable tissue was identified in 44% of the nodules and quantified as 100% in 1% of all lesions, > 75% in 3%, > 50% in 4%, > 25% in 23%. In conclusion, multiple-phase helical CT allows optimal depiction of primitive liver nodules treated with percutaneous interventional procedures and has a central role in the assessment of tumor response. As for the treatment procedures, it was found that thermal ablation with radiofrequency and single-session ethanol-injection cause more evident alterations within both nodule and hepatic parenchyma, while after multi session ethanol injection changes are less dramatic and consequently more difficult to assess. [Italian] Scopo di questo lavoro e' riportare l'esperienza personale sulla valutazione con TC spirale del carcinoma epatocellulare trattato con varie procedure interventistiche percutanee e verificare il valore diagnostico della metodica e i reperti riscontrabili a livello dei noduli e del parenchima epatico sano. Nel periodo dicembre 1996-settembre 1998 si sono esaminati con TC spirale 41 pazienti (complessivamente 73 noduli) con epatocarcinoma sottoposti a procedure ablative percutanee: alcolizzazione tradizionale - 18 pazienti (31 noduli), alcolizzazione con seduta singola - 3 (8 noduli), ipertermia con radiofrequenza - 16 (25 noduli), trattamento combinato chemioembolizzazione e alcolizzazione - 4 (9 noduli). Lo studio con TC e' stato eseguito 4-27 giorni dopo l'ultimo trattemento mediante acquisizione volumetrica bifasica in 14 pazienti e trifasica in 27. In 28 noduli e' stato effettuato nuovo trattamento con successiva indagine con TC; 15 sono stati sottoposti a 3 controlli e 6 a 4 controlli. Rispetto ai reperti pre-trattamento il diametro e' risultato uguale nel 62% dei noduli e maggiore nel 38%. La morfologia e' apparsa immodificata nel 63% delle lesioni mentre nel 37% e' stata rilevata relativa deformazione del versante attraversato dall'ago oppure aspetto piu' regolare e rotondeggiante. I margini sono apparsi invariati nel 37% dei casi e modificati nel 63%, con aspetto regolare nel 73 e irregolare nel 27%. La quota necrotica aveva bassa attenuazione con gradiente densitometrico rispetto al parenchima epatico piu' marcato nella fase tardiva, poi in quella venosa e infine in quella arteriosa; nell'acquisizione diretta l'8% delle lesini non e' risultato riconoscibile. E' stato documentato tessuto neoplastico residuo nel 44% dei noduli e quantitativamente e' risultato del 100% nell'1% delle lesioni totali, >75% nel 3%, >50% nel 4%, >25% nel 12%, <25% nel 23%. Era localizzato centralmente nel 6% dei casi, perifericamente nel 12% ed eccentricamente nell'82%; la sua forma e' risultata semilunare nel 65% dei casi, ovalare nel 19% e con diverso aspetto nel 16%. La TC spirale multifasica consente ottimale valutazione del nodulo epatico primitivo sottoposto a procedure interventistiche percutanee e svolge un ruolo centrale nell'analisi dell'efficacia terapeutica. In relazione con il tipo di procedura si ha che nella termoablazione con radiofrequenza e nell'alcolizzazione con seduta singola le modificazioni sia del nodulo trattato che del parenchima sano sono piu' marcate mentre nell'alcolizzazione multissessione molti aspetti sono meno definiti nel loro(abstract truncated)

  10. Diagnosis of hepatic steatosis by contrast-enhanced abdominal computed tomography; Diagnostico da esteatose hepatica pela tomografia computadorizada de abdome com meio de contraste intravenoso

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    Monjardim, Rodrigo da Fonseca; Costa, Danilo Manuel Cerqueira; Romano, Ricardo Francisco Tavares; Salvadori, Priscila Silveira; Santos, Jaime de Vargas Conde dos; Atzingen, Augusto Castelli Von; Shigueoka, David Carlos; D' Ippolito, Giuseppe, E-mail: giuseppe_dr@uol.com.br [Universidade Federal de Sao Paulo (EPM/UNIFESP), SP (Brazil). Escola Paulista de Medicina. Dept. de Diagnostico por Imagem

    2013-05-15

    Objective: to evaluate the diagnostic capacity of abdominal computed tomography in the assessment of hepatic steatosis using the portal phase with a simplified calculation method as compared with the non-contrast-enhanced phase. Materials and methods: in the present study, 150 patients were retrospectively evaluated by means of non-contrast-enhanced and contrast-enhanced computed tomography. One hundred patients had hepatic steatosis and 50 were control subjects. For the diagnosis of hepatic steatosis in the portal phase, the authors considered a result of < 104 HU calculated by the formula [L - 0.3 Multiplication-Sign (0.75 Multiplication-Sign P + 0.25 Multiplication-Sign A)] / 0.7, where L, P and A represent the attenuation of the liver, of the main portal vein and abdominal aorta, respectively. Sensitivity, specificity, positive and negative predictive values were calculated, using non-contrast-enhanced computed tomography as the reference standard. Results: the simplified calculation method with portal phase for the diagnosis of hepatic steatosis showed 100% sensitivity, 36% specificity, negative predictive value of 100% and positive predictive value of 75.8%. The rate of false positive results was 64%. False negative results were not observed. Conclusion: The portal phase presents an excellent sensitivity in the diagnosis of hepatic steatosis, as compared with the non-contrast-enhanced phase of abdominal computed tomography. However, the method has low specificity. (author)

  11. Segmentação das áreas isquêmicas no acidente vascular cerebral utilizando imagens de tomografia computadorizada de perfusão

    OpenAIRE

    Lilian Contin

    2011-01-01

    As técnicas de processamento digital de imagens têm sido vastamente aplicadas às imagens médicas. Um dos benefícios ocasionado por estas ferramentas é o de prover medidas de parâmetros que são difíceis de estimar e suscetíveis a viés do médico. O presente trabalho teve por objetivo desenvolver um software semi-automático de segmentação das áreas isquêmicas, core e penumbra, no acidente vascular cerebral, utilizando técnicas de segmentação por limiarização e baseada em regiões. Os dois algorit...

  12. Dosimetry for computed tomography using Fricke gel dosimetry and magnetic resonance imaging; Dosimetria em tomografia computadorizada empregando dosimetro Fricke gel e a tecnica de imageamento por ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Capeleti, Felipe Favaro; Campos, Leticia L., E-mail: felipe@gmpbrasil.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2014-04-15

    In this work it was determined a new method for the determination of absorbed doses in Computed Tomography (CT) examinations using Fricke gel dosimetry developed at IPEN. Absorbed doses were determined by different methods of analysis, such as optical absorption spectrometry, ionization chambers and magnetic resonance imaging. Lower limit of sensitivity of the Fricke gel solution, the solution repeatability signal Fricke gel and CT equipment, detection sensitivity, among other tests were performed. Different equipment of computed tomography with multiple detectors were used. The Fricke gel solution showed better repeatability than ±5.5% using the technique of optical absorption spectrophotometry and computed tomography equipment showed repeatability better than ±0.2%. The Fricke gel solution features an easy and relatively quick preparation, but it is necessary to be careful not to contaminate and lose the solution. With the results, it was confirmed the application of this type of dosimetry for computed tomography equipment. (author)

  13. Local behavior and lymph node metastases of Wilms' tumor: accuracy of computed tomography; Comportamento local e metastases linfonodais do tumor de Wilms: acuracia da tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Eduardo Just da Costa e, E-mail: eduardojust@oi.com.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Instituto Materno Infantil de Pernambuco (IMIP), Recife, PE (Brazil); Silva, Giselia Alves Pontes da [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. Maternal Infantil

    2014-01-15

    Objective: to evaluate the accuracy of computed tomography for local and lymph node staging of Wilms' tumor. Materials and methods: each case of Wilms' tumor was evaluated for the presence of abdominal lymph nodes by a radiologist. Signs of capsule and adjacent organ invasion were analyzed. Surgical and histopathological results were taken as the gold standard. Results: sensitivity was 100% for both mesenteric and retroperitoneal lymph nodes detection, and specificity was, respectively, 12% and 33%, with positive predictive value of 8% and 11% and negative predictive value of 100%. Signs of capsular invasion presented sensitivity of 87%, specificity of 77%, positive predictive value of 63% and negative predictive value of 93%. Signs of adjacent organ invasion presented sensitivity of 100%, specificity of 78%, positive predictive value of 37% and negative predictive value of 100%. Conclusion: computed tomography tumor showed low specificity and low positive predictive value in the detection of lymph node dissemination. The absence of detectable lymph nodes makes their presence unlikely, and likewise regarding the evaluation of local behavior of tumors. (author)

  14. Computed tomography evaluation of autogenous graft in sinus lift surgery; Analise por tomografia computadorizada do enxerto autogeno na cirurgia de 'sinus lift'

    Energy Technology Data Exchange (ETDEWEB)

    Ajzen, Sergio Aron; Moscatiello, Rafael Andrade; Lima, Aida Maria Custodio de; Moscatiello, Vitoria Aparecida Muglia; Helio Kiitiro Yamashita [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. de Diagnostico por Imagem; Mosacatiello, Rafael Muglia; Nishiguchi, Celso Itiro [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Disciplina de Tecnica Operatoria e Cirurgia Experimental; Alves, Maria Teresa de Seixas [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Disciplina de Anatomia Patologica

    2001-02-01

    The objective was to quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from apheresis or centrifugation using computed tomography. This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months), with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental implant. All patients were submitted to computed tomography examinations prior and six months after sinus lift surgery. Fifty-three maxillary sinuses were operated and divided into three distinct groups: autogenous bone graft, autogenous bone graft in combination with platelet-rich plasma obtained by centrifugation, and autogenous bone graft in combination with platelet-rich plasma obtained by apheresis. The results showed that computed tomography demonstrated bone growth in height and width between the initial and the follow-up computed tomography scans in all three groups. However, no statistical difference was found either for bone height or width. It was concluded that clinical evidence demonstrates the effectiveness of autogenous bone grafts, particularly when used in combination with bone growth factors such as platelet-rich plasma, which allow prosthetic and functional restoration of maxillofacial structures through fixation of dental implants. (author)

  15. Clinical manifestations in patients with computerized tomography diagnosis of neurocysticercosis; Manifestacoes clinicas de pacientes com diagnostico de neurocisticercose por tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Pfuetzenreiter, Marcia Regina [Universidade do Estado de Santa Catarina (UDESC), Florianopolis, SC (Brazil). Dept. de Medicina Veterinaria Preventiva e Tecnologia]. E-mail: a2mrp@cav.udesc.br; Avila-Pires, Fernando Dias de [Santa Catarina Univ., Florianopolis, SC (Brazil). Dept. de Saude Publica

    1999-09-01

    A survey was conducted in the urban area of Lages using patients who had been submitted to a computed tomography of the skull in the period of March-December, 1996, for different reasons. Forty-two patients with a provisional diagnosis of neurocysticercosis, and 57 negatives were personally interviewed by one of the authors (Pfuetzenreiter), using a semi-structured procedure. More individuals with a provisional diagnostic of neurocysticercosis reported clinical manifestations related to this infection than those found negative. this difference is more marked among women, except in relation to convulsions, more frequently reported by men (19.05%) than by women (7.14%). The greater percentage of inactive forms (83.33%0 and a longer history of perceived symptoms among those positives suggest that the condition is not new. (author)

  16. Bosniak classification of renal cystic lesions according to multidetector computed tomography findings; Classificacao de Bosniak das lesoes cisticas renais segundo achados na tomografia computadorizada multidetectores

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Christiana Maia Nobre Rocha de; Padilha, Igor Gomes; Farias, Lucas de Padua Gomes de; Rocha, Milzi Sarmento da, E-mail: maiachristiana@globo.com [Universidade Federal de Alagoas (UFAL), Maceio, AL (Brazil); Maranhao, Carol Pontes de Miranda; Santos, Carla Jotta Justo dos [Clinica de Medicina Nuclear e Radiologia de Maceio (MedRadiUS), Maceio, AL (Brazil)

    2014-03-15

    Renal cystic lesions are usually diagnosed in the radiologists' practice and therefore their characterization is crucial to determine the clinical approach to be adopted and prognosis. The Bosniak classification based on computed tomography findings has allowed for standardization and categorization of lesions in increasing order of malignancy (I, II, IIF, III and IV) in a simple and accurate way. The present iconographic essay developed with multidetector computed tomography images of selected cases from the archives of the authors' institution, is aimed at describing imaging findings that can help in the diagnosis of renal cysts. (author)

  17. Quantitative computed tomography as a test of endurance for evaluation of bony plates; Utilizacao da tomografia computadorizada quantitativa como teste de resistencia para avaliacao de placas osseas

    Energy Technology Data Exchange (ETDEWEB)

    Melo Filho, E.V.; Costa, L.A.V.S.; Oliveira, D.C. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil); Freitas, P.M.C. [Escola de Veterinaria - Universidade Federal de Minas Gerais - Belo Horizonte, MG (Brazil); Teixeira, M.W.; Costa, F.S. [Universidade Federal Rural de Pernambuco - Recife, PE (Brazil)

    2012-06-15

    Quantitative computed tomography was used to determine the radiodensity of bony plates. The CT scans provided information regarding radiodensity of bony plates and allowed to verify the uniformity of bone mineral density in their scope. The proposed methodology should be considered as another tool for determining the resistance of these biomaterials. (author)

  18. Determination of the dose index in computerized tomography using thermoluminescent dosemeters; Determinacion del indice de dosis en tomografia computada usando dosimetros termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Azorin, J.C.; Calderon, A. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-IPN, 11500 Mexico D.F. (Mexico); Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico)

    2004-07-01

    In this work the obtained results of the determination of the dose index are presented in thorax studies in computed tomography and helical tomography carried out in Mexico using thermoluminescent dosemeters of LiF: Mg,Cu,P + Ptfe developed and manufactured in our country. The results showed that under similar conditions of irradiation and operation (pitch = 1), significant differences don't exist among the doses absorbed measures in the phantom due to the two types of used tomographs. (Author)

  19. Computed tomography with thermal neutrons and gaseous position sensitive detector; Tomografia computadorizada com neutrons termicos e detetor a gas sensivel a posicao

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Maria Ines Silvani

    2001-12-01

    A third generation tomographic system using a parallel thermal neutron beam and gaseous position sensitive detector has been developed along three discrete phases. At the first one, X-ray tomographic images of several objects, using a position sensitive detector designed and constructed for this purpose have been obtained. The second phase involved the conversion of that detector for thermal neutron detection, by using materials capable to convert neutrons into detectable charged particles, testing afterwards its performance in a tomographic system by evaluation the quality of the image arising from several test-objects containing materials applicable in the engineering field. High enriched {sup 3} He, replacing the argon-methane otherwise used as filling gas for the X-ray detection, as well as, a gadolinium foil, have been utilized as converters. Besides the pure enriched {sup 3} He, its mixture with argon-methane and later on with propane, have been also tested, in order to evaluate the detector efficiency and resolution. After each gas change, the overall performance of the tomographic system using the modified detector, has been analyzed through measurements of the related parameters. This was done by analyzing the images produced by test-objects containing several materials having well known attenuation coefficients for both thermal neutrons and X-rays. In order to compare the performance of the position sensitive detector as modified to detect thermal neutrons, with that of a conventional BF{sub 3} detector, additional tomographs have been conducted using the last one. The results have been compared in terms of advantages, handicaps and complementary aspects for different kinds of radiation and materials. (author)

  20. Multislice helical computed tomography in the evaluation of lumbar spine diseases; Tomografia computadorizada 'multislice' no diagnostico das afeccoes da coluna lombar

    Energy Technology Data Exchange (ETDEWEB)

    Rosemberg, Laercio Alberto; Rios, Adriana Martins; Almeida, Milena Oliveira [Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil)]. E-mail: laercio@einstein.br; Garbaccio, Viviane Ladeira; Kim, Nelson Ji Tae; Daniel, Mauro Miguel; Funari, Marcelo Buarque de Gusmao [Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil). Dept. de Imagem

    2003-06-01

    Multislice computed tomography has advantages in comparison to conventional computer tomography such as reduction in study time, lower radiation dose, fewer metal artifacts and high quality multiplanar reformatting and three-dimensional reconstructions. We reviewed approximately 300 lumbar spine examinations and selected the most illustrative cases including congenital anomalies, degenerative lesions, spinal infections, neoplasms traumatic injuries, spondylolysis and postoperative changes. In the majority of the cases the high quality multiplanar reformatted and volume reconstructions of multislice computed tomography allowed better evaluation of the lesions, particularly in the cases of complex anatomy (author)

  1. Experimental study of mechanisms of sand production using X-ray computerized tomography; Estudo experimental dos mecanismos da producao de areia empregando tomografia computadorizada de raios X

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Janaina B.; Vargas Junior, Euripedes [Pontificia Univ. Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil). Dept. de Engenharia Civil; Barroso, Emilio V. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Dept. de Geologia; Campos, Elisabete; Goncalves, Clemente; Tavares, Andre [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    During productive phase of the well, many times there is simultaneous production of the solid particles detached from matrix of the reservoir rock. This phenomenon receives the name of the sand production. In this case stress and flow conditions around of the well are fundamental factors for deflagration of the process. Stress concentration in the wall of the well lead to the loss of cohesion between grains arising, consequently, a granular material region susceptible for dragging by seepage forces derived from fluid flow. The objective of this work was to perform sand production tests in Rio Bonito and synthetic sandstone samples using real-time X-Ray Computerized Tomography. The tests investigated the initial and the evolution of failure at the cavity wall of samples. These are initial stages of the sand production process. The analysis of the CT-scans obtained during tests allowed the visualization of breakouts and collapses of the wells. From studies more details were possible estimate the sand production and produce 3-D images of the propagation of the failure. (author)

  2. Optic coherence tomography in a patient with diffuse unilateral subacute neuroretinitis Tomografia de coerência óptica em neuretinite subaguda difusa unilateral

    Directory of Open Access Journals (Sweden)

    Alexandre Henrique Gomes

    2009-04-01

    Full Text Available PURPOSE: To measure retinal nervous fiber layer (RNFL thickness using OCT3 (Carl-Zeiss in patients with diffuse unilateral subacute neuroretinitis (DUSN with or without live worm and correlate it with visual acuity. METHODS: RNFL thickness, using RNFL thickness 3.4 program and best corrected visual acuity were measured in patients with DUSN between January 2005 and December 2006. RESULTS: Thirty-eight patients, aged 9 - 42 years were selected, of whom 20 had live worm. Mean RNFL was 71.55 ± 27.26 in the DUSN eye and 103.07 ± 20.66 in the contralateral eye (pOBJETIVO: Avaliar o uso do OCT3 (Carl-Zeiss para medir a espessura da camada de fibras nervosas em pacientes com neuroretinite unilateral subaguda difusa (DUSN e correlacionar com a acuidade visual. MÉTODOS: Foi medido a espessura da camada de fibras nervosas, utilizando programa "RNFL thickness 3.4" e a melhor acuidade visual de pacientes com DUSN entre janeiro de 2005 e dezembro 2006. RESULTADOS: Trinta e oito pacientes, com idade entre 9-42 anos foram selecionados para este estudo, sendo que 20 casos apresentavam larva viva localizada. A média da RNFL foi 71,55 ± 27,26 nos olhos com DUSN e 103,07 ± 20,66 nos olhos contralaterais (p<0,001. Correlação de Pearson entre a acuidade visual e a espessura da camada de fibras nervosas foi r= -0,522 (p<0,001 nos olhos com DUSN e r= -0,097 (p=0,509 nos olhos contralaterais. CONCLUSÃO: A espessura da camada de fibras nervosas de pacientes com DUSN apresenta uma correlação diretamente proporcional com a acuidade visual. Novos estudos são necessários para reforçar a correlação entre a acuidade visual e a espessura da camada de fibras nervosas nos pacientes com DUSN com a finalidade de acompanhar os pacientes após o tratamento.

  3. Pulmonary malaria: high-resolution computed tomography findings - a case report; Malaria pulmonar: aspectos na tomografia computadorizada de alta resolucao - relato de caso

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Rosana; Souza, Daniel Andrade Tinoco de [Universidade Federal, Rio de Janeiro, RJ (Brazil). Hospital Universitario Clementino Fraga Filho. Servico de Radiodiagnostico; Hospital Copa D' Or, Rio de Janeiro, RJ (Brazil); Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia]. E-mail: edmarchiori@bol.com.br

    2004-04-01

    We report the case of a 38-year-old man with pulmonary malaria. High-resolution computed tomography showed thickening of the peribronchovascular interstitium and interlobular septa, areas of consolidation and ground glass attenuation and bilateral pleural effusion suggesting pulmonary edema. The patient recovered well after receiving specific treatment and was discharged after 11 days of hospitalization. (author)

  4. Computed tomography of mast cell tumors in dogs: assessment before and after chemotherapy; Tomografia computadorizada de mastocitomas em caes: avaliacao pre e pos-tratamento quimioterapico

    Energy Technology Data Exchange (ETDEWEB)

    Lorigados, Carla A.B.; Matera, Julia Maria; Pinto, Ana Carolina B.C.F.; Macedo, Thais R., E-mail: clorigados@usp.br [Universidade de Sao Paulo (FMVZ/USP), SP (Brazil). Fac. de Medicina Veterinaria e Zootecnia. Dept. de Cirurgia; Coppi, Antonio A.; Ladd, Fernando V.L. [Universidade de Sao Paulo (LSSCA/USP), SP (Brazil). Fac. de Medicina Veterinaria e Zootecnia. Lab. de Estereologia Estocastica e Anatomia Quimica; Souza, Vanessa A.F. de [Faculdades Metropolitanas Unidas (FMU), Sao Paulo, SP (Brazil). Curso de Medicina Veterinaria

    2013-11-15

    Nineteen dogs with mast cell tumors treated with chemotherapy were evaluated by computed tomography (CT). Were evaluated aspects related to contours, attenuation, postcontrast enhancement and presence of cleavage with adjacent structures. The RECIST criteria and volumetric measurement of lesions were performed to assess the response to treatment. The mast cell tumors presented a homogeneous or heterogeneous attenuation, presented more frequently a well delineated and regular contours and moderate enhancement after intravenous administration of the iodinated contrast media. The methods RECIST and volumetric measurements showed an excellent agreement to the classification of therapeutic response, providing a good parameter of the response to treatment. The CT examination proved to be useful in the delimitation of the tumor and an important tool for planning of surgical margins. (author)

  5. Pediatric computed tomography dose of head and chest exams: a bibliography revision; Dose em exames de cranio e torax de tomografia computadorizada pediatrica: uma revisao bibliografica

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, Barbara Q.; Capaverde, Alexandre S.; Vanni, Stefania; Mazzola, Carolina F.S.; Silva, Ana M. Marques da, E-mail: barbara.friedrich@acad.pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil)

    2015-08-15

    The Computed Tomography (CT) imaging diagnosis it is responsible for over 34% of the radiation dose given to society, only in Brazil there is around 3833 CT equipment. There are two dose index in CT, the CTDI{sub vol} and DLP that represents the Computed Tomography dose index and the product of the CTDI{sub vol} by the length of irradiation. This paper has as objective describe the values of CTDI{sub vol} e DLP for pediatric exams of chest and head. This is an exploratory study of bibliography revision on the PubMed data base using the index terms with the following crossing: Computed Tomography AND Reference Levels AND Dose. The search was limited by published studies on the last 5 years with patients among 0 and 15 years, in English or Portuguese. Besides that, were included references guides suggest by scientific and governmental organizations on the last 5 years. The data analysis was made using the four readings of Gil: exploratory, selective, analytic and interpretative. By the Exploratory Reading were located 23 articles. On the Selective Reading were excluded 4 articles and on the Analytic Reading 9 articles. The Interpretative Reading was made using 7 publications. Regarding the references guides were includes 3 guides. The Portaria MS453/98 was included for being the only national publication. All data were characterized between practical levels and reference levels. The conclusion is that there is no consensus between the reference levels for the selected articles, for pediatric exams. Besides that, the national legislation do not have reference levels for pediatric CT. (author)

  6. Multidetector-row helical computed tomography in the evaluation of cervical spine disorders; Tomografia computadorizada multislice no diagnostico das afeccoes da coluna cervical

    Energy Technology Data Exchange (ETDEWEB)

    Rosemberg, Laercio Alberto; Almeida, Milena Oliveira; Rios, Adriana Martins; Garbaccio, Viviane Ladeira; Kim, Nelson Ji Tae; Daniel, Mauro Miguel; Funari, Marcelo Buarque de Gusmao [Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil). Dept. de Imagem]. E-mail: laercio@einstein.br

    2003-07-01

    Multidetector-row computed tomography (MRCT) has advantages in comparison to conventional helical computed tomography, such as reduction of study time, lower radiation doses, fewer metallic artifacts and high quality multiplanar reformatting and three dimensional reconstructions. We reviewed 150 cervical spine examinations and selected the most illustrative cases including congenital anomalies, degenerative lesions, spinal infections, neoplasms, traumatic injuries and postoperative abnormalities. The quality of multiplanar reformatting and volume reconstructions of the MRCT made the detection and evaluation of most of cases with complex anatomy easier and more precise. (author)

  7. Aortic non communicating dissections. A study with helical CT; Studio dell'ematoma intramurale aortico. Aspetti con Tomografia Computerizzata spirale

    Energy Technology Data Exchange (ETDEWEB)

    Midiri, M.; Strada, A.; Stabile Ianora, A.A.; Rotondo, A.; Angelelli, G. [Bari Univ., Bari (Italy). Dipt. di Medicina Interna e Medicina Pubblica, Sez. di Diagnostica per Immagini; Scialpi, M. [Ospedale SS. Annunziata, Taranto (Italy); D' Agostino, D.; De Luca Tupputi Schinosa, L. [Bari Univ., Bari (Italy). Dipt. Emergenze Trapianto d' Organo, Sez. di Cardiochirurgia

    2000-09-01

    The evaluate the signs of aortic intramural hematoma with helical CT and the diagnostic role of this technique in patients with this condition. It was reviewed the CT findings of 396 patients submitted to emergency examinations for suspected aortic dissection from 1995 to 1999. Only 18 patients (6 women and 12 men) had CT signs of aortic intramural hematoma. Helical CT studies were carried out with the following parameters: slice thickness 10 mm, reconstruction index 10, feed 1.5 mm, conventional algorithm with minimum values of 130 kV and 125mA. All patients were examined with dynamic contrast-enhanced CT, before and after a power injection of 130 mL ionic contrast material. It was studied: hematoma localization and longitudinal extension; thickness and density of aortic wall; presence and location of intimal calcifications; integrity of intimal wall; hemo mediastinum and/or hemo thorax. Aortic wall thickening appeared as a high density crescent-shaped area at baseline CT and had low density on enhanced images in all patients. Thickening was eccentric in 14/18 patients and concentric in 4/18 only; it always exceeded 4 mm. It was found some intimal calcifications in 8 patients and hemo thorax and/or hemo mediastinum in 9 patients. A patient with type A hematoma died of cardiac tamponade a few hours after CT diagnosis. Six patients (5 type B and 1 type A) underwent anti-hypertensive treatment and radiological follow-up. Eleven patients (6 type A and 5 type B) underwent prosthesis replacement and 5 of them (3 type A and 2 type B) died of postoperative complications. In the 5 type B patients surgery was performed because of treatment-resistant pain and of the onset of ischemic complications to abdominal organs caused by involvement of the main collateral branches of the aorta. One patient with type A hematoma was submitted to drug treatment because it was judged unresectable. Intramural hematoma of the aorta is a distinct pathological entity, which should not be confused with aortic dissection. The imaging techniques (TEE, CT, MRI) have an important role in the final diagnosis of aortic hematoma. Presently Helical CT and MR angiography are the main tools in the early diagnosis of this condition before the development of complications. In this experience helical CT, before and after the administration of contrast material, was accurate in identifying the hematoma localization and extension. [Italian] Tale studio ha lo scopo di valutare con tecnica TC spirale gli aspetti semeiologici dell'ematoma intramurale dell'aorta e sottolineare il ruolo diagnostico decisivo di tale metodica nello studio di pazienti con quadro clinico acuto sospetto per dissezione aortica. E' stato condotto uno studio retrospettivo (dal 1995 al 1999) sulle immagini di 396 pazienti che avevano eseguito un esame TC in regime d'urgenza per sospetta dissezione aortica. Solo 18 pazienti (6 femmine, 12 maschi) presentavano aspetti tomodensitometrici caratteristici per ematoma intramurale aortico. Gli esami sono stati condotti tutti con TC spirale utilizzando i seguenti parametri: spessore dello strato 10 mm, image index 10, passo della spirale 1,5 mm, algoritmo standard con un minimo di 130 kV e 125 mA. Gli esami sono stati condotti prima e dopo iniezione di 130 ml di mdc in bolo rapido e ricercando i seguenti parametri: sede ed estensione longitudinale dell'ematoma spessore e densita' della parte aortica, presenza e localizzazione delle caclificazioni intimali, regolarita' del lume vero, presenza di emomediastino e/o emotorace. In tutti i 18 pazienti (8 di tipo A e 10 di tipo B) e' stato osservato ispessimento circoscritto parietale tipicamente iperdenso nelle scansioni di base e ipodenso in quelle dopo mdc. In 14/18 pazienti l'ispessimento assumeva disposizione eccentrica, in solo 4/18 era concentrico; in tutti i casi l'ispessimento e' risultato maggiore di 4 mm. In 18/18 pazienti sono state riscontrate calcificazioni intimali e in 9/18 era presente emomediastino e/o emotorace sinistro. Un paziente con ematoma di tipo A e' deceduto per tamponamento cardiaco qualche ora dopo la diagnosi TC. Sei pazienti (5 di tipo B e 1 di tipo A) sono stati sottoposti a terapia medica con farmaci antiipertensivi e monitoraggio radiologico. Undici pazienti (6 di tipo A e 5 di tipo B) sono stati sottoposti a intervento chirurgico di sostituzione protesica; di questi, 5 (3 di tipo A e 2 di tipo B) sono deceduti per complicazioni postoperatorie. L'indicazione all'intervento chirurgico nei 5 casi di ematoma tipo B si e' basata sull'insorgenza di dolore refrattario alla terapia antiipertensiva e insorgenza di complicazioni ischemiche degli organi addominali per interessamento delle maggiori arterie collaterali dell'aorta, mentre un caso di ematoma di tipo A e' stato trattato farmacologicamente poiche' considerato inoperabile. La diagnostica per immagini svolge un ruolo fondamentale nella diagnosi di ematoma intramurale (ecografia transeso-fagea, TC, RM).

  8. Idiopathic pulmonary fibrosis and collagen vascular diseases - high resolution CT findings; Pneumopatias intersticiais difusas idiopaticas e associadas a colagenoses - aspectos da tomografia computadorizada de alta resolucao

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira Neto, Armando Leao; Mogami, Roberto [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Centro Biomedico. Inst. de Radiologia; Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. Biomedico. Dept. de Radiologia; Capone, Domenico [Universidade Estadual, Rio de Janeiro, RJ (Brazil). Dept. de Penumologia

    1996-09-01

    The aspects of the thorax high-resolution computed tomography of 15 patients with idiopathic pulmonary fibrosis and 11 patients with collagen vascular diseases are described and characterized mainly by the presence of reticular lesions with little cysts predominantly in the periphery and lower lobes. They may be associated with ground-glass lesions that, as usual, means areas of alveolitis. (author) 31 refs., 5 figs.

  9. Tomography by positrons emission: integral unit to the service of Mexico; Tomografia por emision de positrones: unidad integral al servicio de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Lopez D, F A [Unidad PET-Ciclotron, Facultad de Medicina, UNAM (Mexico)

    2005-07-01

    The applications of the Positron emission tomography (PET) together with the one radiopharmaceutical 2 - [{sup 18} F]-fluoro-2-deoxy-D-glucose in the area of the medical imaging is expanding quickly and it possesses a bigger impact at the moment in favor of those patient to who suffers an oncological, cardiac or neurological illness in Mexico. (Author)

  10. Diffuse lung neoplasms. Correlation between high resolution computerized tomography and anatomopathology; Neoplasias pulmonares difusas: correlacao da tomografia computadorizada de alta resolucao com a anatomopatologia

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia; Irion, Klaus L. [Complexo Hospitalar Santa Casa de Porto Alegre, RS (Brazil). Servico de Radiologia do Pavilhao Pereira Filho; Souza Junior, Arthur Soares [Faculdade de Medicina de Sao Jose do Rio Preto, SP (Brazil)]. E-mail: edmarchiori@zipmail.com.br

    2002-08-01

    A short comparative evaluation study between high resolution computerized tomography and anatomopathologic findings is presented. The association of these two diagnostic techniques is discussed as a factor to enhance the accuracy of diffuse lung diseases, such as carcinomatous lymphangitis, Kaposi's Sarcoma, lymphomas, hematogenic metastases, bronchiole-alveolar carcinoma and leukemia. (MAC)

  11. Computed tomography of the dog's brain: normal aspects and anatomical correlation; Tomografia computadorizada do encefalo do cao: aspectos da normalidade e correlacao anatomica

    Energy Technology Data Exchange (ETDEWEB)

    Lorigados, C.A.B., E-mail: clorigados@usp.br [Faculdades Metropolitanas Unidas (UniFMU), Sao Paulo, SP (Brazil); Pinto, A.C.B.F. [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia

    2013-06-15

    Normal tomographic images of dog's heads were obtained, aimed to familiarize them with the normal aspects of the brain and correlate these findings with the relevant anatomy of the region studied. Several anatomical structures, such as the parenchyma of the frontal, parietal, temporal and occipital lobes, the longitudinal fissure, the ventricular system, the cerebellum, the olfactory bulb, the corpus callosum, diencephalon, the pons, the medulla oblongata and the chiasmatic sulcus were directly identified or were related to neighboring structures which helped in their identification. (author)

  12. Optical coherence tomography signal analysis: LIDAR like equation and inverse methods; Analise de sinais de tomografia por coerencia optica: equacao LIDAR e metodos de inversao

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, Marcello Magri

    2012-07-01

    Optical Coherence Tomography (OCT) is based on the media backscattering properties in order to obtain tomographic images. In a similar way, LIDAR (Light Detection and Range) technique uses these properties to determine atmospheric characteristics, specially the signal extinction coefficient. Exploring this similarity allowed the application of signal inversion methods to the OCT images, allowing to construct images based in the extinction coefficient, original result until now. The goal of this work was to study, propose, develop and implement algorithms based on OCT signal inversion methodologies with the aim of determine the extinction coefficient as a function of depth. Three inversion methods were used and implemented in LABView{sup R}: slope, boundary point and optical depth. Associated errors were studied and real samples (homogeneous and stratified) were used for two and three dimension analysis. The extinction coefficient images obtained from the optical depth method were capable to differentiate air from the sample. The images were studied applying PCA and cluster analysis that established the methodology strength in determining the sample's extinction coefficient value. Moreover, the optical depth methodology was applied to study the hypothesis that there is some correlation between signal extinction coefficient and the enamel teeth demineralization during a cariogenic process. By applying this methodology, it was possible to observe the variation of the extinction coefficient as depth function and its correlation with microhardness variation, showing that in deeper layers its values tends to a healthy tooth values, behaving as the same way that the microhardness. (author)

  13. Determination of the initial energy in computerized tomography with proton beams; Determinacao da energia inicial em tomografia computadorizada com feixe de protons

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Rodrigo Luis da

    2007-07-01

    In earliest works devoted to proton computed tomography it was shown that the advantage of pCT image reconstruction appears when the energy is close to the Bragg peak region, since the proton passes the object. This effect provided by the Bragg peak makes the computerized tomography with protons possible. However, when decreasing the initial proton energy, with the increase of the irradiation dose, there are two effects that work simultaneously in opposite ways. First, the energy loss of a proton in an object becomes bigger at small initial energy. At the same time decreasing of the proton energy results in the increase of the energy straggling, requiring a larger number of protons. In this work the radiation dose dependence on the proton initial energy was studied using analytical formulas and computer simulations. The investigation determined that the radiation dose practically does not depend on the initial energy, except in the energy region very close to the minimum energy necessary to pass the object. (author)

  14. Dosimetry in Computed Tomography head and neck scans; Dosimetria em varreduras de Tomografia Computadorizada de cabeça e pescoço

    Energy Technology Data Exchange (ETDEWEB)

    Gómez, A.M.L.; Santana, P.C.; Mourão, A.P., E-mail: amlgphys@gmail.com [Universidade Federal de Minas Gerais (UFMG), Berlo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2017-07-01

    Non-invasive diagnostic methods for X-rays, such as computed tomography (CT), have shown rapid growth in radiology services. There is concern about the radiation doses deposited in patients because the CT scans are the ones that contribute most to the dose increase in the population. The legislation for regulating patient dose levels only imposes an upper limit for a given test, depending on the region of the body to be irradiated. Therefore, it is necessary to know the dose values deposited in patients referring to routine protocols used in radiology services and propose an optimization of these according to the principles of radiological protection. Experiments were performed to determine the dose profile deposited in routine adult patient head scans using a male anthropomorphic simulator. Radiochromic film strips were introduced in the central region of the simulator to record the dose profile in the head and neck region and thus determine the air kerma values within the simulator object. Four scans were performed on a General Electric 64-channel tomograph programmed in helical mode and the scans were made with voltages of 80, 100 and 120 kV, and fixed current and automatic current control were used. The mean values recorded on the strips ranged from 14.82 to 22.98 mGy. Imaging noise analyzes were performed so that for all the scans the images obtained were considered of diagnostic quality and the Kerma values in the air when converted to absorbed dose are diagnostic parameters acceptable in the Brazilian legislation.

  15. Evaluation of the normal thoracic and abdominal aorta diameters by computerized tomography; Avaliacao dos diametros normais da aorta toracica e abdominal pela tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Lucarelli, Claudio Luiz

    1995-07-01

    The study was undertaken to evaluate, through computerized tomography, the diameters of the normal thoracic and abdominal aorta, as well as they are connected to gender, age and body surface area; and the ratio between measurements obtained at the ascending and descending limbs of the thoracic aorta, and between the abdominal aortic diameters. For that reason, we measured the widest anteroposterior diameters of the thoracic aortas at the levels of the arch, the root, the pulmonary artery, and the thoracic-abdominal transition, as well as the level of the emergence of the superior mesenteric artery, of the renal hila and just cephalad to the bifurcation of the abdominal aortas of 350 patients without cardiovascular diseases who had undergone computerized tomography of the thorax and/or abdomen for any other reasons. Observation and statistic analyses led us to conclude that: 1) both the thoracic and abdominal aortic diameters are reduced from their proximal to their distal portions; 2) the body surface influences the size of the aorta, although only extreme variations alter the vessel's caliber; 3) vessel diameter was observed to gradually increase with age; 4) men were found to have larger diameters than age matched women; 5) the ratio between the ascending and descending aortic diameters varies according to gender and age; 6) the relations between abdominal aortic diameters measured at the level of renal hila and cephalad to the bifurcation are independent from gender and age. But the relation between those measured at the level of the superior mesenteric artery and cephalad to the bifurcation are linked to gender, but not to age. (author)

  16. Wavelets in quantification of liver tumors in contrasted computed tomography images; Wavelets na quantificacao de tumores de figado em exames contrastados de tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Bruna T.; Alvarez, Matheus; Souza, Rafael T.F.; Miranda, Jose R.A., E-mail: matheus@ibb.unesp.br [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Instituto de Biociencias. Departamento de Fisica e Biofisica; Romeiro, Fernando G. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Fac de Mediciana. Departamento de Clinica Medica; Pina, Diana R. de; Trindade, Andre Petean [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Fac. de Medicina. Departamento de Doencas Tropicais e Diagnostico por Imagem

    2012-12-15

    This paper presents an original methodology of liver tumors segmentation, based on wavelet transform. A virtual phantom was constructed with the same mean and standard deviation of the intensity of gray presented by the measured liver tissue. The optimized algorithm had a sensitivity ranging from 0.81 to 0.83, with a specificity of 0.95 for differentiation of hepatic tumors from normal tissues. We obtained a 96% agreement between the pixels segmented by an experienced radiologist and the algorithm presented here. According to the results shown in this work, the algorithm is optimal for the beginning of the tests for quantification of liver tumors in retrospective surveys. (author)

  17. Evaluation of doses received by pediatric and adult patients undergoing to CT exams; Evaluacion de la dosis recibida por pacientes adultos y pediatricos en examenes de tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Lavie, Maria F. Jimenez; Tejeda, Adalberto Machado, E-mail: felicia@cceem.sld.cu, E-mail: adalberto@cceem.sld.cu [Centro para el Control Estatal de Medicamentos, Equipos y Dispositivos Medicos (CECMED), La Habana (Cuba); Otano, Anisia; Zuniga, Dora Maya [Hospital Pediatrico Centro Habana (Cuba); Perdomo, Jorge Hing; Rodriguez, Gustavo Guadarrama [Hospital Docente Clinico Quirurgico Freyre Andrade, La Habana (Cuba)

    2013-07-01

    This paper aims to evaluated the dose to adult and pediatric patients due to the execution of tests CT scan of head, chest and abdomen, as well as establish a comparative analysis between these results and protocols involving employees to begin a process optimization in the practice.

  18. Automatic 2D segmentation of airways in thorax computed tomography images; Segmentacao automatica 2D de vias aereas em imagens de tomografia computadorizada do torax

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcante, Tarique da Silveira; Cortez, Paulo Cesar; Almeida, Thomaz Maia de, E-mail: tarique@lesc.ufc.br [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Engenharia de Teleinformatica; Felix, John Hebert da Silva [Universidade da Integracao Internacional da Lusofonia Afro-Brasileira (UNILAB), Redencao, CE (Brazil). Departamento de Energias; Holanda, Marcelo Alcantara [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Fac. de Medicina

    2013-07-01

    Introduction: much of the world population is affected by pulmonary diseases, such as the bronchial asthma, bronchitis and bronchiectasis. The bronchial diagnosis is based on the airways state. In this sense, the automatic segmentation of the airways in Computed Tomography (CT) scans is a critical step in the aid to diagnosis of these diseases. Methods: this paper evaluates algorithms for airway automatic segmentation, using Neural Network Multilayer Perceptron (MLP) and Lung Densities Analysis (LDA) for detecting airways, along with Region Growing (RG), Active Contour Method (ACM) Balloon and Topology Adaptive to segment them. Results: we obtained results in three stages: comparative analysis of the detection algorithms MLP and LDA, with a gold standard acquired by three physicians with expertise in CT imaging of the chest; comparative analysis of segmentation algorithms ACM Balloon, ACM Topology Adaptive, MLP and RG; and evaluation of possible combinations between segmentation and detection algorithms, resulting in the complete method for automatic segmentation of the airways in 2D. Conclusion: the low incidence of false negative and the significant reduction of false positive, results in similarity coefficient and sensitivity exceeding 91% and 87% respectively, for a combination of algorithms with satisfactory segmentation quality. (author)

  19. Method of evaluation of diagnostics reference levels in computerized tomography; Metodo de avaliacao de niveis de referencia de radiodiagnostico em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Vega, Walter Flores

    1999-04-01

    Computerized tomography is a complex technique with several selectable exposition parameters delivering high doses to the patient. In this work it was developed a simple methodology to evaluate diagnostic reference levels in computerized tomography, using the concept of Multiple Scan Average Dose (MSAD), recently adopted by the Health Ministry. For evaluation of the MSAD, a dose distribution was obtained through a measured dose profile on the axial axis of a water phantom with thermoluminescence dosemeters, TLD-100, for different exam technique. The MSAD was evaluated hrough two distinct methods. First, it was evaluated by the integration of the dose profile of a single slice and, second, obtained by the integration on central slice of the profile of several slices. The latter is in of accordance with the ionization chamber method, suggesting to be the most practical method of dose evaluation to be applied in the diagnostic reference level assessment routine for CT, using TLDs. (author)

  20. Study of the effect of the variation of automatic exposure control in computed tomography; Estudio del efecto de la variacion del control automatico de exposicion en tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Nersissian, D. Y.; Capeleti, F. F.; Furquin, T. A. C.; Melo, C. S.

    2011-07-01

    Teams computed tomography (CT) contain the current automatic control of exposure (CAE) which vary from the current X-ray tube in clinical protocols and deliver lower doses than those with fixed current. Alone is not enough control of dose, you need an acceptable image quality ensuring an accurate diagnosis. The TC regulate the flow of two ways: by considering the thickness of the patient and the attenuation by different tissues that intercept the x-ray Besides the advantage, there is the responsibility of proper use of different CAE systems, which require particular knowledge of each manufacturer of the CT.

  1. Epiploic appendicitis and omental infarction. Findings in the ultrasonography and computerized tomography; Apendicitis epiploica e infarto omental. Hallazgos en ecografia y tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Migule, A.; Ripolles, T.; Martinez, M. J.; Morote, V.; Ruiz, A. [Hospital Universitario Dr. Peset. Valencia (Spain)

    2001-07-01

    Describe the findings in the ultrasonography and computerized tomography (CT) of the omental infarction and epiploic appendicitis. The clinical and radiological findings of the patients diagnosed in our hospital with epiploic appendicitis or omental infarctions between August 1994 and March 2001 were assessed retrospectively. We found a high incidence (42 cases) of these two diseases: 30 patients with diagnosis of epiploic appendicitis and 12 with the diagnosis of omental infarction. Four patients were treated surgically, while the remaining 38 were conservatively, without posterior complications. The ultrasonography and CT images is characteristics. making it possible to make a diagnosis of epiploic appendicitis or omental infarction with certainty. It is not necessary to make a differential diagnosis between the two entities because their prognosis and treatment are similar. Their incidence is much more frequent than that previously published. (Author) 19 refs.

  2. Automatic detection of flaws in polymer insulators using 3D industrial tomography; Deteccao automatica de vazios em isoladores polimericos por tomografia industrial 3D

    Energy Technology Data Exchange (ETDEWEB)

    Godoi, Walmor Cardoso; Swinka-Filho, Vitoldo [Instituto de Tecnologia para o Desenvolvimento (LACTEC), Curitiba, PR (Brazil)], Emails: walmor@lactec.org.br, vitoldo@lactec.org.br; Geus, Klaus de [Companhia Paranaense de Energia (Copel), Curitiba, PR (Brazil)], Email: klaus@copel.com; Silva, Romeu Ricardo da [SENAI-RJ Solda (CTS/Solda), Rio de Janeiro, RJ (Brazil). Centro de Tecnologia], Email: rrdsilva@firjan.org.br

    2009-10-15

    This work presents a methodology for the automatic detection of flaws in polymer insulators using three-dimensional industrial computed tomography (CT), as well as results obtained in the context of power distribution networks. The CT slices were reconstructed using 180 digital radiographs (projections) acquired by a high resolution system (pixel dimension of 50 {mu}m x 50 {mu}m, a-Si). For the reconstruction of 3D CT, 50 {mu}m wide bit map slices were used. The Marching Cubes algorithm was used to perform the 3D reconstruction, using the Visualization Tool kit (VTK) library and the Java programming language (64 Bits Linux platform). Nine features were obtained from the reconstructed three-dimensional objects for the neural networks training. Results showed to be satisfactory. (author)

  3. Relationship between CT scans and serum tests for diagnosing tuberculosis; Relacao entre imagens de tomografia computadorizada e exames sericos no diagnostico da tuberculose

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Marcela de; Pina, Diana R.; Giacomini, Guilherme; Alvarez, Matheus; Pavan, Ana Luiza M.; Pereira, Paulo C.M. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil)

    2014-07-01

    Tuberculosis (TB) is one of the oldest infectious diseases in the world and still affects humanity today. Since 1993, the World Health Organization (WHO) considers TB as a global emergency. The clinical history of the individual, the serum exams and particularly, the imaging examination of the thorax, are used for diagnostic confirmation and monitoring of disease. TB is a chronic disease that usually evolves with pulmonary sequelae that must be monitored. The exam of the image more precise to assess the radiological patterns found in these patients is high-resolution computed tomography (HRCT), which aids in medical diagnosis and permit the determination of the area affected by radiological abnormalities of pulmonary tuberculosis. The best known of such modifications by means of exams or more accurate techniques is of extreme importance. Therefore, this study aimed to show the quantification, performed by algorithms, of the areas affected by the radiological abnormalities of TB through the HRCT, and compared with serum exams. We studied 16 patients with confirmed diagnosis of TB. The serum exams evaluated included: hemoglobin, hematocrit, albumin, speed hemo sedimentation and C-reactive protein. With the values of serum exams we observed that patients have anemia, low albumin levels and inflammatory activity, corroborating imaging exams, which show severe impairment of lung area due to the inflammation caused by disease activity. (author)

  4. CT assessment of thoracic gunshot wounds. Our personal experience; Ruolo della Tomografia Computerizzata nelle lesioni da arma da fuoco del torace. Esperienza personale

    Energy Technology Data Exchange (ETDEWEB)

    Salzano, A.; De Rosa, A. [Ospedale Loreto Mare, Neaples (Italy). Servizio di Radiologia; Carbone, M.; Rossi, E.; Burnese, L. [Neaples Univ., Neaples (Italy). Ist. di Scienze Radiologiche; Muto, M.; Tuccillo, M. [Azienda Ospedaliera di Rilievo Nazionale A. Cardarelli, Neaples (Italy). Servizio di Neuroradiologia, 2 Servizio di Radiologia; Nunziata, A. [Pronto Soccorso Est, ASL NA1, Neaples (Italy). Area di Diagnostica per Immagini

    1999-11-01

    CT is a valuable tool in assessing thoracic gunshot wounds. CT is also the method of choice in emergency, because it permits rapid depiction of bullet damage to the chest and to other body districts. This in turn permits correct assessment of the main thoracic injuries, plus adequate and prompt planning of surgical treatment or support intensive care. It is reported on the role of CT in diagnosing the complex pleuropulmonary, cardiovascular and thoracic wall injuries caused by gunshot wounds, with their specific and acute signs which differ greatly fro those of other types of chest trauma. In the last 4 years, it was observed an amount of 76 cases of gunshot injury, twenty-six of them involved the chest. The patients, 25 men and 1 woman (mean age: 32 years, range: 17-48), were all submitted to emergency CT with iv contrast agent injection and the CT-angiography technique. The reanimator was always presented to monitor the patients' vital functions and shock state. CT of the chest was integrated with CT of the abdomen and pelvis in 4 cases and with CT of the skull in 3 cases, to detect associated bullet wounds if any. Chest radiography shows major gunshot wound damage to the chest and lungs, except for heart injuries and minimal pneumothorax. When abdominal and skull injuries are associated, CT should be the method of choice because it permits prompt and panoramic assessment of the severity of pulmonary and extra thoracic damage. This results in prompt and targeted treatment, avoiding unnecessary delays which may damage the patient further. [Italian] L'impiego della TC nella valutazione del paziente con lesioni da arma da fuoco del torace risulta essenziale e prioritario rispetto ad altre metodiche di diagnostica per immagini, poiche' consente di avere la rapida visione d'insieme dei danni provocati dal proiettile nel suo impatto con le strutture toraciche e con altri distretti corporei coinvolti. Cio' permette il corretto inquadramento delle principali lesioni interne con adeguata e istantanea pianificazione del trattamento chirurgico d'emergenza e/o rianimativo di supporto. Scopo del presente lavoro e' quello di illustrare il ruolo dell'esame TC nel documentare le molteplici e complesse lesioni pleuropolmonari, cardiovasali e della parete toracica, la cui compromissione si manifesta con semeiologia specifica e acuta del tutto diversa da quella della traumatologia toracica classica. Negli ultimi 4 anni sono stati osservati presso il pronto soccorso dell'Ospedale Loreto Mare di Napoli 76 casi di ferite d'arma da fuoco, di cui 26 con interessamento toracico: 25 maschi e una femmina (eta' media 32 anni, compresa tra 17 e 48 anni). Tutti i pazienti sono stati sottoposti a TC d'urgenza del torace con iniezione endovenosa di mdc e con tecnica angio-TC e in presenza del medico rianimatore con monitoraggio delle funzioni vitali e dello stato di shock. In 4 casi e' stato completato con studio TC dell'addome e pelvi per la presenza di lesioni associate toraco-addominali e in 3 casi con TC del cranio per lesioni encefaliche da proiettile. Il radiogramma del torace consente di documentare i danni maggiori toraco-polmonari d'arma da fuoco, anche se non permette la valutazione precisa delle lesioni cardiache e dei grandi vasi e dei pneumotoraci minimali. L'associazione di alterazioni traumatiche cranio-addominali concomitanti indirizza l'approccio diagnostico verso una metodica di primo livello come la TC, in grado di fornire con un unico esame il giudizio immediato sul grado di compromissione, panoramicita' e gravita' delle lesioni da arma da fuoco polmonari e extratoraciche. Cio' consente di instaurare la terapia tempestiva e mirata, sia essa chirurgica o di supporto rianimativo, evitando ritardi diagnostici e di gestione terapeutica sicuramente dannosi per la sopravvivenza del paziente.

  5. Liver trauma from penetrating injuries. Miscellanea, personal series, clinical and CT findings; Traumi epatici da lesioni penetranti. Miscellanea, casistica personale, aspetti clinici e con Tomografia Computerizzata

    Energy Technology Data Exchange (ETDEWEB)

    Salzano, A.; Nocera, V. [Ospedale San Giovanni di Dio di Frattamaggiore, Servizio di Radiologia, Frattamaggiore, NA (Italy); De Rosa, A.; Vigliotti, A. [Azienda Sanitaria Locale NA1, Radiologia, Naples (Italy); Rossi, E.; Carbone, M.; Gatta, G. [Naples Univ. Federico 2., Naples (Italy). Ist. di Scienze Radiologiche; Vitale, L. [Ospedale di Sorrento, Servizio di Radiologia, Sorrento, NA (Italy)

    2000-12-01

    Penetrating liver wounds are related to many causes and rank second after blunt abdominal and liver trauma. In this report are examined the clinical and radiological findings of personal series of patients with penetrating trauma, especially by firearms and stab and cut wounds. It will also tried to define the diagnostic workup of these traumas, which is especially based on CT signs of liver damage and associated changes and which is of basic importance for following treatment, both surgical or conservative. In the last seven years it was retrospectively reviewed 31 cases of penetrating liver trauma. The patients were 19 men and 12 women, ranging in age 18 to 73 (mean 42), with penetrating liver injuries from firearms (16 patients) and stab (9 cases) wounds; 6 patients had injuries from different cases. Abdominal CT was carried out in emergency with the CT Angiography (CTA) technique in all patients. In the patients with suspected chest and abdomen involvement CT was performed from the mid-chest for accurate assessment of diaphragm and lung bases and to exclude associated pleuropulmonary damage. Penetrating liver wounds were caused by firearms in 70% of cases, by stabbing in 12% and, in the extant 18%, by other cases such as home accidents, road and work traumas, and liver biopsy. In this series, the liver was most frequently involved, especially by firearms wounds; in the 16 cases the most frequent injuries were hemorrhagic tears. It was found bullets in the liver in 6 cases. In one case of home accident the patient wounded himself while slicing bread with a long knife, which cut into the anterior abdominal wall and tore the anterior liver capsule, as seen at CTA. Penetrating wounds to liver and abdomen are less frequent than those to the chest. In the past decade the use of CT has changed the diagnostic and therapeutic approach to such injuries completely, decreasing the resort to explorative laparotomy and hepatorrhaphy. Indeed, CT provides a clear picture of the extent and severity of damage, which permits to choose a conservative treatment in case of intraparenchymal hematomas and lacerocontusive foci without hemoperitoneum, which can be followed-up with physical and CT examinations. Moreover, Helical CT could provide the early diagnosis of active bleeding in the peritoneum and of focal bleeding in the liver, thus permitting prompt hepatorrraphy or targeted hepatectomy. A diaphragm injury suspected at CT should always prompt the surgeon to intervention, especially when hemothorax, lung base pneumothorax, large liver hematoma or tear of the liver dome are associated. Finally, subdiaphragmatic free gas indicates gut perforation associated with liver damage, in which case surgery is necessary too. [Italian] Le ferite penetranti del fegato sono dovute a molteplici cause, e occupano il secondo posto dopo i traumi chiusi epato-addominali. Scopo del lavoro e' di illustrare i vari quadri clinico-radiologici della nostra casistica personale, determinati da lesioni penetranti da armi da fuoco e da punta e taglio. Definire inoltre la modalita' di diagnosi, soprattutto in base ai segni TC del danno epatico e di lesioni associate, che condizionano in modo decisivo la terapia e l'approccio chirurgico o conservativo. Negli ultimi sette anni sono stati studiati retrospettivamente 31 casi (19 maschi e 12 femmine; eta' media 42 anni, compresa tra 18 e 73 anni), con lesioni penetranti del fegato, dovute prevalentemente a armi da fuoco (16 pazienti), a armi da punta e taglio (9 casi) e miscellanee in 6. L'esame TC dell'addome e' stato eseguito in emergenza e con tecnica angio-TC in tutti i pazienti. Nei casi di ferite con sospetto coinvolgimento toraco-addominale, la TC veniva iniziata dal medio-torace al fine di una valutazione accurata del diaframma, delle basi polmonari e per escludere lesioni pleuropolmonari associate. Nel 70% dei casi le ferite penetranti epatiche erano in relazione ad arma da fuoco, nel 12% da punta e taglio, e nel 18% per cause varie come incidenti domestici, traumi della strada, del lavoro e agobiopsie epatiche. Nel nostro studio TC, il fegato e' risultato l'organo maggiormente coinvolto nei traumi penetranti dell'addome, con maggiore frequenza per le ferite da arma da fuoco; nei 16 casi osservati, le lesioni parenchimali piu' comuni erano lacerazioni emorragiche. I proiettili ritenuti nell'organo sono stati riscontrati in 6 casi. In un caso di incidente domestico il paziente si era provocato una vasta ferita penetrante della parete addominale anteriore, affettando del pane con un lungo coltello, con lacerazione capsulare anteriore del fegato documentata con TC. Le ferite penetranti del fegato e dell'addome sono meno frequenti di quelle toraciche. Nell'ultimo decennio il ricorso alla metodica TC per la valutazione del danno epatico nelle ferite penetranti ha cambiato radicalmente l'approccio diagnostico e terapeutico, riducendo la frequenza delle laparotomie esplorative e abstract truncated)

  6. Evaluation of the normal thoracic and abdominal aorta diameters by computerized tomography; Avaliacao dos diametros normais da aorta toracica e abdominal pela tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Lucarelli, Claudio Luiz

    1995-07-01

    The study was undertaken to evaluate, through computerized tomography, the diameters of the normal thoracic and abdominal aorta, as well as they are connected to gender, age and body surface area; and the ratio between measurements obtained at the ascending and descending limbs of the thoracic aorta, and between the abdominal aortic diameters. For that reason, we measured the widest anteroposterior diameters of the thoracic aortas at the levels of the arch, the root, the pulmonary artery, and the thoracic-abdominal transition, as well as the level of the emergence of the superior mesenteric artery, of the renal hila and just cephalad to the bifurcation of the abdominal aortas of 350 patients without cardiovascular diseases who had undergone computerized tomography of the thorax and/or abdomen for any other reasons. Observation and statistic analyses led us to conclude that: 1) both the thoracic and abdominal aortic diameters are reduced from their proximal to their distal portions; 2) the body surface influences the size of the aorta, although only extreme variations alter the vessel's caliber; 3) vessel diameter was observed to gradually increase with age; 4) men were found to have larger diameters than age matched women; 5) the ratio between the ascending and descending aortic diameters varies according to gender and age; 6) the relations between abdominal aortic diameters measured at the level of renal hila and cephalad to the bifurcation are independent from gender and age. But the relation between those measured at the level of the superior mesenteric artery and cephalad to the bifurcation are linked to gender, but not to age. (author)

  7. Survey of computed tomography doses in head and chest protocols; Levantamento de doses em tomografia computadorizada em protocolos de cranio e torax

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Giordana Salvi de; Silva, Ana Maria Marques da, E-mail: giordana.souza@acad.pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Faculdade de Fisica. Nucleo de Pesquisa em Imagens Medicas

    2016-07-01

    Computed tomography is a clinical tool for the diagnosis of patients. However, the patient is subjected to a complex dose distribution. The aim of this study was to survey dose indicators in head and chest protocols CT scans, in terms of Dose-Length Product(DLP) and effective dose for adult and pediatric patients, comparing them with diagnostic reference levels in the literature. Patients were divided into age groups and the following image acquisition parameters were collected: age, kV, mAs, Volumetric Computed Tomography Dose Index (CTDIvol) and DLP. The effective dose was found multiplying DLP by correction factors. The results were obtained from the third quartile and showed the importance of determining kV and mAs values for each patient depending on the studied region, age and thickness. (author)

  8. Survey of computed tomography doses in head and chest protocols; Levantamento de doses em tomografia computadorizada em protocolos de cranio e torax

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Giordana Salvi de; Froner, Ana Paula Pastre; Silva, Ana Maria Marques da, E-mail: giordana.souza@acad.pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Faculdade de Fisica. Nucleo de Pesquisa em Imagens Medicas

    2016-07-01

    Surveys of dose estimates from different medical imaging modalities highlight significant variations between health care facilities for the same examination and similar patient groups. To ensure that doses are optimized, diagnostic reference levels (DRL) must be determined, allowing the identification of procedures that are out of optimal standards. The aim of this study is to present a retrospective survey of dose indicators in head and chest CT scans, in terms of Dose-Length Product (DLP) and effective dose for adult and pediatric patients, comparing them with DRL in the literature. The study was performed with data from 293 patients submitted to computed tomography of the skull and 146 of the thorax, divided into age groups (0⊣ 1; 1⊣ 5; 5⊣ 10; 10⊣ 15; >15. For head, DLP third percentiles and effective doses are mostly higher than DRL in literature, mainly for children from 10⊣15 years (800 mGy.cm; 3,3 mSv) and 5⊣ 10 years (969 mGy.cm; 2,6 mSv). For thorax examination, although DLP are close to the DRL in literature, high variability is revealed, and the effective doses are higher for all ages. In conclusion, the survey of dose indicators in computed tomography examinations and their comparison with DRL constitute an important tool for the optimization of doses in patients. (author)

  9. Aspects of pulmonary histiocytosis X on high resolution computed tomography; Aspectos da histiocitose X pulmonar na tomografia computadorizada de alta resolucao (TCAR)

    Energy Technology Data Exchange (ETDEWEB)

    Costa, N.S.S.; Castro Lessa Angela, M.T. de; Angelo Junior, J.R.L.; Silva, F.M.D.; Kavakama, J.; Carvalho, C.R.R. de; Cerri, G.G. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina. Hospital das Clinicas. Inst. do Coracao

    1995-01-01

    Pulmonary histiocytosis X is a disease that occurs in young adults and presents with nodules and cysts, mainly in upper lobes, with consequent pulmonary fibrosis. These pulmonary changes are virtually pathognomonic findings on high resolution computed tomography, that allows estimate the area of the lung involved and distinguish histiocytosis X from other disorders that also produces nodules and cysts. (author). 10 refs, 2 tabs, 6 figs.

  10. Hypersensitivity pneumonitis (extrinsic allergic alveolitis): high-resolution computed tomography findings; Pneumonite por hipersensibilidade (alveolite alergica extrinseca): achados na tomografia computadorizada de alta resolucao

    Energy Technology Data Exchange (ETDEWEB)

    Almeida Junior, Jose Guiomar de; Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Faculdade de Ciencias Medicas. Dept. de Radiologia]. E-mail: edmarchiori@zipmail.com.br; Escuissato, Dante L. [Parana Univ., Curitiba, PR (Brazil). Dept. de Radiologia; Souza Junior, Arthur Soares [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Radiologia; Gasparetto, Emerson L. [Parana Univ., Curitiba, PR (Brazil). Hospital de Clinicas; Nobre, Luiz Felipe [Santa Catarina Univ., Florianopolis, SC (Brazil); Irion, Klaus L. [Santa Casa de Misericordia de Porto Alegre, RS (Brazil). Pavilhao Pereira Filho. Servico de Radiologia

    2003-12-01

    Hypersensitivity pneumonitis, or extrinsic allergic alveolitis, is an immunologic disease of the lungs caused by inhaled chemicals or organics allergens. A lymphocytic inflammatory response in the peripheral airways and surrounding interstitial tissue occurs. In this study the high-resolution computed tomography findings of 13 patients with hypersensitivity pneumonitis were analyzed and discussed. The most frequent high-resolution computed tomography findings were: ground-glass opacities (92.3%), centrilobular nodules (38.4%) and air trapping (38.4%). Other findings included bronchiectasis (23.1%), consolidation (23.1%), crazy paving (7.7%), parenchymal bands (15.4%), linear opacities (7.7%), architectural distortion (7.7%), tracheal dilatation (7.7%), intralobular reticulate (7.7%), honeycombing (7.7%), emphysema (7.7%) and atelectasis (7.7%). In two of the 13 patients there was fibrosis (architectural distortion and honeycombing), which represents the chronic phase of the disease. (author)

  11. Anatomic relationship of the optic nerve channel with sphenoid al sinus: a computed tomography study; Relacao anatomica do nervo optico com o seio esfenoidal: estudo por tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Paulo Cesar J. [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil); Albernaz, Pedro Luiz M. [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. de Otorrinolaringologia e Disturbios da Comunicacao Humana; Yamashida, Helio K. [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. de Diagnostico por Imagem

    2004-09-15

    The sphenoid sinus, out of the facial sinuses, is certainly the most neglected as far as diagnosis is concerned. The surgical approach requires a detailed anatomical knowledge, considering the serious complications resulting from injuries of vital structures adjacent to this region. Aim: the objective of our research is to evaluate the anatomic relationship of the optic nerve with the sphenoid sinus making use of the computed tomography. Study design: series report. Material and method: the authors present a retrospective analysis of 203 computed tomographies of facial sinus belonging to individuals of both sexes aged 14 and over. The examinations were evaluated observing the course of the optic nerve, obtained through the degree of its projection on the wall of the sphenoid sinus. The method used was the modified classification of Delano, evaluating the absence of bone reduction (dehiscence) of the optic nerve in the sphenoid sinus. We analysed the degree of pneumatization of the sphenoid sinus, using Hammer's classification adapted by Guerrero, apart from the pneumatization of the anterior clinoidal process and pterigoid and the presence of the Onodi cell. Results: most of the patients (78.96%) presented their optic nerve with a type 1 course. Type 2 was observed in 16.83% of the patients, type 3 in 3.47% and type 4 in 0.74%. The presence of dehiscence of the optic nerve in the wall of the sphenoid sinus was evidenced in 21.29% of the cases. Related to pneumatization, we noticed that the pre-selar type was observed in 6.44%, the post-selar type appeared in 39.11%, the selar type appeared in 54.45%, and the apneumatized type was not observed in any of the cases. The pneumatization of the anterior clinoidal process was verified in 10.64% of the cases, while the pterigoid process was apparent in 21.29% of the cases. The Onodi cell (sphenoetmoidal) was found in 7.92% of the cases. Conclusion: the presence of dehiscence of the optic nerve is related with the degree of pneumatization of the anterior clinoid and the pterigoid processes, the presence of the Onodi cell (sphenoetmoidal) and course types 2, 3 and 4 considered the relationship between the optic nerve and the sphenoid sinus. (author)

  12. Program standard of quality control for a system of Positron Emission Tomography-computed tomography (PET-CT) used in the Foundation Valle de Lili; Programa estandar de control de calidad para un sistema de tomografia por emision de positrones-tomografia computadorizada (PET-CT) utilizado en la Fundacion Valle del Lili

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, Nathalia I.; Benavides, Sivor O., E-mail: Nnunez@fcvl.org, E-mail: Obenavides@fcvl.org [Fundacion Valle del Lili (OFM-PR/FVL), Cali (Colombia). Dept. de Fisica Medica y Proteccion Radiologica; Lopera, Wilson, E-mail: wilson.lopera@correounivalle.edu.co [Universidad del Valle, Cali (Colombia). Dept. de Fisica

    2013-07-01

    A standard protocol of quality control in the Fundacion Valle del Lili for the implementation of a multimodal scanner developed emission tomography BIOGRAPH mCT X-3R of SIEMENS Registered-Sign covering routine testing, frequency, acceptance ranges necessary corrective and preventive measures to detect and correct any faults and proceed if the upper detection precision and accuracy ranges accepted deviations actions. In order to minimize errors in the planning and management of patient dose, thereby improving the quality of the diagnostic image with the dose of radiation is reasonably low as possible, consistent with the clinical use of the equipment used and the information requested diagnostic study.

  13. Discrete instability in the DNA double helix

    International Nuclear Information System (INIS)

    Tabi, Conrad Bertrand; Mohamadou, Alidou; Kofane, Timoleon Crepin

    2009-06-01

    Modulational instability (MI) is explored in the framework of the base-rotor model of DNA dynamics. We show in fact that, the helicoidal coupling introduced in the spin model of DNA reduces the system to a modified discrete sine-Gordon (sG) equation. The MI criterion is thus modified and displays interesting features because of the helicoidal coupling. This is confirmed in the numerical analysis where a critical value of the helicoidal coupling constant is derived. In the simulations, we have found that a train of pulses are generated when the lattice is subjected to MI, in agreement with analytical results obtained in a modified discrete sG equation. Also, the competitive effects of the harmonic longitudinal and helicoidal constants on the dynamics of the system are notably pointed out. In the same way, it is shown that MI can lead to energy localization which is high for some values of the helicoidal coupling constant. (author)

  14. Comparision between biphasic helical CT and dynamic gadolinium-enhanced MR in the detection and characterization of focal hepatic lesions in cirrhotic patients; Estudio comparativo entre TC helicoidal bifasica y RM dinamica con gadolinio en la deteccion y caracterizacion de lesiones focales hepticas en pacientes cirrticos

    Energy Technology Data Exchange (ETDEWEB)

    Puig, J; Martn, J; Donoso, L; Falco, J; Rue, M [Consorcio Hospitalario del Parc Taul. Sabadell. Barcelona (Spain)

    1998-12-31

    To assess the agreement between biphasic helical computerized tomography (BHCT) and dynamic gadolinium-enhanced magnetic resonance (MR) in the detection and characterization of focal hepatic lesions in a group of cirrhotic patients. A prospective study was done in 50 cirrhotic patients suspected of having hepatocarcinoma (HC) on the basis of ultrasonographic images evaluated by means of BHCT and dynamic gadolinium-enhanced MR using fast low-angle shot (FLASH) sequences (110-135/4/90 degree centigree). The images were assessed jointly by four radiologists. Between the two techniques, a total of 83 lesions were detected. MR disclosed more lesions (n=79) than BHCT (n=67) (p<0.005). Moreover, 25 of the lesions that were visible by both techniques were more clearly evident in MR images (p<0.01). MR correctly classified 6 of 7 benign lesions (85%) and 49 of 66 malignant ones (74%). BHCT correctly classifed 2 of 7 benign lesions (28%) and 32 of 66 malignant ones (48%). The sensitivities of MR and BHCT for the characterization of these lesions were 74% and 48%, respectively (p=0.0009), while the respective specificities were 86% and 29% (P<0.001). Dynamic gadolinium-enhanced MR with FLASH sequences is more efficient than BHCT in the detection and characterization of focal lesions in cirrhotic patients. (Author) 37 refs.

  15. Bistable switching in dual-frequency liquid crystals

    Energy Technology Data Exchange (ETDEWEB)

    Palto, S. P., E-mail: palto@online.ru; Barnik, M I [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2006-06-15

    Various bistable switching modes in nematic liquid crystals with frequency inversion of the sign of dielectric anisotropy are revealed and investigated. Switching between states with different helicoidal distributions of the director field of a liquid crystal, as well as between uniform and helicoidal states, is realized by dual-frequency waveforms of a driving voltage. A distinctive feature of the dual-frequency switching is that the uniform planar distribution of the director field may correspond to a thermodynamically equilibrium state, and the chirality of an LC is not a necessary condition for switching to a helicoidal state.

  16. Evaluation of standard and use tendency of image diagnosis exams in Brazil with emphasis in pediatric computerized tomography; Avaliacao do padrao e tendencia de uso de exames de diagnostico por imagem no Brasil com enfase em tomografia computadorizada pediatrica

    Energy Technology Data Exchange (ETDEWEB)

    Dovales, Ana Cristina Murta

    2016-07-01

    There is little information on developing countries about the use of diagnostic imaging procedures and the doses associated with radiological examinations. This study assessed the pattern and trend of diagnostic imaging usage in outpatients of the Brazilian Unified Health System (SUS) by modality and examined body part. Emphasis was given to computed tomography (CT) scans for which the analysis was extended to the private health care sector and included the evaluation of age at examination distribution, and dose estimation for children and young adults. Information on the use of diagnostic imaging procedures among SUS outpatients was obtained from the Outpatient Information System (SIA) of the Department of Information Technology of SUS (DATASUS). Data on the use of CT in the private health care sector were extracted from the Radiological Information Systems (RIS) of 25 private radiology services in 8 Brazilian cities. Effective doses and absorbed doses on organs of interest were estimated individually for 4,497 patients younger than 20 years of age using CT scan technical parameters and Monte Carlo simulations of radiation transport. Between 2002 and 2012 it was observed that conventional radiology was the most frequent modality of diagnostic imaging in SUS outpatients, but more sophisticated modalities, such as CT and magnetic resonance imaging, had the highest growth rates over the study period. The most frequent CT scan in SUS outpatients between 2001 and 2011 was the head/neck exam, but abdomen/pelvis examinations were the ones that grew the most. Patients up to 20 years of age made approximately 13% and 9% of the CT examinations between 2008 and 2014 in the public and private health care systems, respectively. About one-third of the private-sector patients had more than one CT scan in this period. There was great variation in doses, even for the same type of procedure in patients of the same age group. The highest mean effective dose was 13.5 mSv estimated for abdomen/pelvis CT in children younger than one year of age. The highest absorbed doses were estimated for the brain after head/neck CT (23.8 to 29.0 mGy), which was the most common type of CT in children and young adults in the study period. The intense increase, the magnitude of the estimated doses and the large proportion of pediatric CT scans in Brazil point out to the need for initiatives to promote appropriate justification and optimization of these examinations in Brazil. (author)

  17. Pneumocystis carinii pneumonia in acquired immunodeficiency syndrome - correlation of high-resolution computed tomography and anatomopathology; Pneumocistose na sindrome da imunodeficiencia adquirida: correlacao da tomografia computadorizada de alta resolucao com a anatomopatologia

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson; Moreira, Luiza Beatriz [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia]. E-mail: edmarchiori@zipmail.com.br; Capone, Domenico [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Faculdade de Medicina; Moraes, Heleno Pinto de [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Patologia; Pereira, Cyntia Inez Guedes Soares

    2001-12-01

    We present the main findings observed on the high-resolution computed tomography examinations of 15 patients with acquired immunodeficiency syndrome and Pneumocystis carinii pneumonia. The high-resolution computed tomography and autopsy findings of 5 patients were also compared. The most frequently observed high-resolution computed tomography patterns were ground-glass attenuation, consolidation areas, crazy-paving pattern and cysts. Nodules and intralobular reticulation were less frequently observed. Ground-glass attenuation and consolidation areas corresponded to alveolar filling with inflammatory exudate. Thickening of the interlobular septa was due to cell infiltration and edema. One patient presented interlobular reticulation, and the pathology study revealed alveolar septa thickening due to cell infiltration and fibrosis. Nodules observed in one of the patients corresponded to a patchy intra alveolar accumulation of microorganisms and inflammatory cells forming a 'granulomatous' pattern. (author)

  18. Role of Spiral and Multislice Computed Tomography in the evaluation of traumatic and spontaneous oesophageal perforation. Our experience; Ruolo della Tomografia Computerizzata Spirale e Multistrato nello studio delle lesioni traumatiche e spontanee dell'esofago: nostra esperienza

    Energy Technology Data Exchange (ETDEWEB)

    De Lutio di Castelguidone, Elisabetta; Pinto, Antonio; Merola, Stefanella; Stavolo, Ciro; Romano, Luigia [Azienda Ospedaliera di Rilievo Nazionale A. Cardarelli, Napoli (Italy). Dipartimento di Diagnostica per Immagini

    2005-03-01

    Purpose: To assess the role of CT in the evaluation of traumatic and spontaneous oesophageal perforation. Materials and methods: From March 2001 to May 2003, we studied 12 patients (7 males and 5 females; age range: 25-66 years, mean age: 43.5 years) with suspected oesophageal perforation due to motor-vehicle accidents (4 cases), stab wound (one case), post-intubation (2 cases), foreign body ingestion (2 cases) and spontaneous (3 cases). Five patients underwent standard chest and cervical radiography; two patients with suspected foreign body ingestion also underwent a gastrografin swallow study; all of the 12 patients underwent CT of the neck, chest and abdomen before and after intravenous, and in four cases oral, administration of contrast material. Results: In 5 patients with cervical, thoracic and abdominal trauma, the CT examination showed the presence of pleuroparenchymal injury (pneumothorax, pleural effusion and subcutaneous emphysema) as well as findings suggestive of oesophageal perforation: peri-oesophageal air (5 cases), peri-oesophageal fluid (4 cases), oesophageal wall thickening (3 cases), oesophageal wall laceration (2 cases) with abnormal course of the nasogastric tube in one of them and extraluminal extravasation of oral contrast material (2 cases). In two patients with post-intubation complications, CT showed the presence of a small peri-oesophageal fluid collection containing small gas bubbles in one case, and a gross peri-oesophageal abscess-like collection in the second case. In the 2 patients with foreign body ingestion, the plain radiography associated with CT showed the presence of a thin metal object in the cervical region (fragment of a dental plate) and a small extraluminal extravasation of gastrografin in one case, whereas in the other case CT showed the presence of a foreign body (chicken bone) in the hypopharynx with oesophageal wall thickening and peri-oesophageal oedema. In the remaining three patients with suspected spontaneous oesophageal perforation, CT showed the presence of a intramural haematoma in one case, oesophageal fluid distension with gas and a small peri-oesophageal fluid effusion (Mallory-Weiss syndrome) in another, and oesophageal rapture (Boerhaave syndrome) in the last case. Conclusions: Our experience shows that in patients with suspected traumatic and spontaneous oesophageal perforation, standard cervical and chest radiography may suggest a suspected oesophageal perforation in only a small proportion of cases, whereas oral contrast oesophagography has a higher sensitivity. Through the careful analysis of suggestive and specific signs of oesophageal perforation, a correct CT examination enables an accurate and timely diagnosis which significantly affects prognosis and provides valuable indications for treatment. [Italian] Scopo: Presentare la nostra esperienza relativa al ruolo della TC nello studio delle perforazioni traumatiche e spontanee dell'esofago. Materiale e metodi: Da marzo 2001 a maggio 2003 sono giunti alla nostra osservazione 12 pazienti (7 di sesso maschile, 5 di sesso femminile, di eta' compresa tra 25 e 66 anni, eta' media 43,5) con sospetta lesione esofagea da incidente stradale (in 4 casi), ferita d'arma bianca (un caso), post-intubazione (2 casi), da indigestione di corpo estraneo (2 casi) e di tipo spontaneo (3 casi). Cinque pazienti praticavano l'esame standard del torace e della regione cervicale. In 2 pazienti con sospetta indigestione di corpo estraneo veniva somministrato gastrografin per os. In tutti i 12 casi veniva eseguito l'esame TC del collo-torace-addome senza e con mdc ev e con mdc idrosolubile per os in 4 casi. Risultati: Nei 5 pazienti con trauma cervico-toracico-addominale l'indagine TC evidenziava oltre a lesioni traumatiche pleuro-parenchimali (pneumotorace, versamento pleurico ed enfisema sottocutaneo) anche reperti suggestivi di perforazione esofagea: aria mediastinica in sede periesofagea (5 casi), fluido periesofageo (4 casi), ispessimento parietale dell'esofago (3 casi), lacerazione della parete esofagea (2 casi), con anomalo decorso del sondino naso gastrico in uno, e stravaso extraluminale del mdc per os (2 casi). In 2 pazienti con complicanze post-intubazione, l'esame TC mostrava una modesta raccolta fluida periesofagea con piccole bolle gassose nel contesto in un caso e nell'altro una grossolana raccolta mista di tipo ascessulae in sede periesofagea. Nei 2 pazienti con riferita ingestione di corpo estraneo, l'esame diretto cervico-toracico integrato da quello TC, evidenziava in un caso la presenza, in sede cervicale, di sottile corpo estraneo metallico (frammento di protesi dentaria) e minimo stravaso extraluminale di gastrografin, mentre nel secondo paziente, l'esame TC mostrava la pesenza di corpo estraneo (piccolo osso di pollo) a sede ipofaringea con ispessimento parietale dell'esofago ed edema dei tessuti circostanti. Nei rimanenti 3 casi con sospetta lesione spontanea dell'esofago, la TC evidenziav ain un caso la presenza di un ematoma intramurale, in un altro caso sovradistensione fluida dell'esofago con nucleo gassoso e piccola soffusione fluida periesofagea (indicativi di sindrome di Mallory-Weiss) e nel terzo caso la rottura dell'esofago (sindrome di Boerhaave). Conclusioni: Dalla nostra esperienza emerge che nella valutazione dei pazienti con sospetta lesione traumatica o spontanea dell'esofago, l'esame radiologico standard della regione cervicale e del torace puo' suggerire il sospetto di perforazione esofagea in una bassa percentuale di casi, mentre lo studio contrastografico dell'esofago per os presenta una sensibilita' piu' elevata. La TC, infine, eseguita con tecnica accurata, consente, attraverso una attenta analisi di tutti i segni suggestivi e specifici di lesione esofagea, di formulare una diagnosi corretta nella maggioranza dei casi influenzando la prognosi in modo determinante e fornendo indicazioni preziose per il tipo di management da adottare.

  19. Evaluation of multiple scan average dose (MSAD) levels in computerized tomography in Minas Gerais state, Brazil; Avaliacao dos niveis de dose media em cortes multiplos (MSAD) em tomografia computadorizada no estado de Minas Gerais

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, Thessa C., E-mail: alonso@cdtn.br [Centro de Desenvolvimento de Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Vieira, Leandro de A.; Barbosa, Nayra V.; Oliveira, Jeyselaine R. de; Cesar, Adriana C.Z. [Secretaria de Vigilancia Sanitaria de Minas Gerais, Belo Horizonte, MG (Brazil); Silva, Teogenes A. da [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear. Programa de Ciencias e Tecnicas Nucleares

    2014-07-01

    Computed Tomography (CT) grows every year and is a diagnostic method that has revolutionized radiology with advances in procedures for obtaining image. However, the indiscriminate use of this method generates relatively high doses in patients. The diagnostic reference levels (DRLs) is a practical tool to promote the evaluation of existing protocols. The optimization and the periodic review of the protocols are important to balance the risk of radiation. The present study aims to conduct a survey of levels of MSAD of Minas Gerais following the procedures recommended by current Brazilian law. (author)

  20. Radiological protection in pelvis studies by computed tomography in Rando phantom by means of thermoluminescent dosimetry; Proteccion radiologica en estudios de pelvis por tomografia computada en fantoma Rando mediante dosimetria termoluminiscente

    Energy Technology Data Exchange (ETDEWEB)

    Madrid G, O. A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Calz. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Azorin N, J., E-mail: riveramt@hotmail.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)

    2011-11-15

    The risks of the radiation in computed tomography (CT) studies have been recently reported in many works. Caution should be had in the environment of the exploration in the patient. To maintain the radiation doses so low as is reasonably possible during the CT examination, is important that in the CT the parameters are correctly adjusted for each patient with the purpose of having the minimum dose in the application of the study. Thermoluminescent dosimeters were used to measure the absorbed dose and to measure the CT profiles of dose. The distribution of the dose in the CT abdominal examination in the simulated patients was evaluated. The exploration parameters of the CT were 130 kV, 90 m A, with a cut thickness of 3 mm and a field of 1.0 in the pitch. The assignment dose was increased in an axis along the direction of the study, they were also studied. The equivalent dose due to the direct and dispersed radiation was determined during the procedures of the irradiation in pelvis examinations, for the next areas to the study like is in specific the critical organ (gonads) that is the terminal area of the exploration. During this study of 26 cuts was obtained an equivalent dose to critical organ of 14.27 mSv. (Author)

  1. The angiogram sign in pulmonary atelectasis studied with helical Computed Tomography. Incidence and value; Il segno dell'angiogramma nelle atelettasie polmonari studiate con Tomografia Computerizzata spirale. Incidenza e validita' semeiologica

    Energy Technology Data Exchange (ETDEWEB)

    Sandomenico, F.; Catalano, O.; Cusati, B.; Esposito, M.; Siani, A. [Ospedale S. Maria delle Grazie, Pozzuoli, NA (Italy). Servizio di Radiologia

    1999-12-01

    In this issue it has been investigated the yield of Helical CT in the study of lung vessels, the incidence of the angiogram sign and its actual value. July 1997 to December 1998, were studied 30 cases of pulmonary collapse of different origin. It was found 15 cases of passive collapse (10 from pleural effusion, 2 from diaphragmatic compression, 2 from traumatic pneumothorax, and 1 from isthmic aortic aneurysm), 12 cases of obstructive collapse (9 from bronchogenic carcinoma, 1 from mucoid obstruction, 1 from ilar lymphadenopathy, and 1 from mediastinal cancer), 2 cases of adhesive collapse and 1 case of round atelectasis. All the examinations were performed with the Helical technique during nonionic iodinated contrast agent injection (bolus, 300-350 mg/mL); it was used an automatic injector set at 2-3 mL/s. It was studied the images for the angiogram sign, that is hyperdense bands, usually longer than 2 cm, through the collapsed lung, which correspond to normal pulmonary vascular branches. The angiogram sign was found in 95% of passive (14/15) and in 80% of obstructive (10/12) collapses. The angiogram sign was missing in 1 of 2 adhesive collapses because of vascular distortion from irradiation-related fibrosis. The comet-tail vascular pattern was seen in round atelectasis. It was not found cases of cicatricial collapse. Thanks to its fast acquisition capabilities. Helical CT well depicts peak vascular enhancement, which permitted identification of the angiogram sign in several pulmonary collapse cases. Thus, this sign becomes even less specific, and just one of the signs of pulmonary consolidation. [Italian] Obiettivo di questo articolo e' riportare la validita' della TC spirale nello studio della vascolarizzazione polmonare discutendo sull'incidenza del segno dell'angiogramma nelle atelettasie polmonari e sulla sua effettiva validita' semeiologica. Nel periodo luglio 1997-dicembre 1998 sono stati diagnosticati 30 casi consecutivi di atelettasia polmonare con origine differente. Quindici casi di atelettasia da compressione (10 da versamento pleurico, 2 da sollevamento diaframmatico di cui uno con lacerazione, 2 da pneumotorace post-traumatico, uno da aneurisma dell'istmo aortico), 12 casi di atelettasia da ostruzione (9 da carcinoma broncogeno di cui uno con polmonite post-ostruttiva, uno da ostruzione bronchiale mucosa, uno da linfoadenopatie ilo-mediastiniche ed uno da neoplasia mediastinica), 2 casi di atelettasia adesiva e uno di atelettasia rotonda. Tutti gli esami sono stati condotti utilizzando la tecnica spirale durante iniezione di mdc iodato non ionico (concentrazione 300-350 mg/ml) somministrato a bolo tramite iniettore automatico con velocita' variabile da 2 a 3 ml/s. In accordo con i dati riportati nella letteratura e' stato ricercato il segno dell'angiogramma: strie iperdense solitamente con lunghezza superiore a 2 cm decorrenti nel contesto delle consolidazioni atelettasiche e corrispondenti a normali diramazioni vascolari polmonari. Il segno dell'angiogramma e' stato riscontrato nel 95% dei casi di atelettasia compressiva (14 su 15) e nell'80% delle forme di atelettasia ostruttiva (10 su 12). In 2 casi di atelettasia ostruttiva sono state comunque rilevate iperdensita' puntiformi da strutture vascolari documentate nella sezione trasvesa. Caratteristica l'identificazione delle strutture vascolari a coda di cometa nella forma di atelettasia rotonda. Non sono stati individuati casi di atelettasia cicatriziale. La TC spirale grazie alla notevole rapidita' di acquisizione consente di documentare l'opacizzazione vascolare al momento del picco del bolo contrastografico. Cio' ha reso possibile il riscontro frequente del segno dell'angiogramma nelle atelettasie polmonari. Tale segno, quindi, perde ulteriormente in specificita' semeiologica divenendo unicamente un elemento di colollario nella semeiologia TC delle consolidazioni polmonari rappresentando la regola e non l'eccezione.

  2. The crescent and the periluminal halo: Two Computed Tomography signs of aortic aneurysm impending rupture?; La semiluna e l`alone periluminale: Due segni con Tomografia Computerizzata di aneurisma aortico a rischio di rottura?

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    Catalano, Orlando; Cusati, Bianca [Naples, Univ. ``Federico II`` (Italy). Istituto di Scienze Radiologiche; Rotondo, Antonio [Bari, Univ. (Italy). Facolta` di Medicina

    1997-04-01

    Purpose: To assess the prevalence, significance and practical value of two recently described CT signs of instable aneurysm: the crescent sign and the periluminal halo (a low-attenuating internal layer of the thrombus around the patent lumen). Material and methods: Among the CT examination performed in the last 5 years, they retrospectively selected the nonruptured aneurysms with a diameter exceeding 4 cm (no. = 93 average diameter 5.1 cm, unenhanced images in 28 cases and enhanced in 84) and the ruptured aneurysms (no. = 16, average diameter 6.7 cm, unenhanced images in 9 cases and enhanced in 9). They studied the prevalence of the crescent and halo sing, their relationship with the aneurysm diameter, and the effect of contrast enhancement. Results: The crescent sign was identified with a statistically significant prevalence in ruptured ( 37.5 % or cases) over asymptomatic aneurysms (5.5 %); the halo had the same frequency in the 2 groups (12.5 % and 9.5 %). Both signs were more frequent in bigger aneurysms and were recognizable without differences in unenhanced and enhanced images. Conclusions: The crescent sign, though not exclusive of aneurysmal rupture, indicates instability and its detection should lead to careful follow-up or surgical repair. The halo seems to have no real value as risk factor.

  3. Computed Tomography of gunshot wounds to the head. Personal experience in 23 cases. Ferite da arma da fuoco del cranio osservate con Tomografia Computerizzata. Esperienza personale in 23 casi

    Energy Technology Data Exchange (ETDEWEB)

    Salzano, A.; De Rosa, A. (Ospedale Loreto Mare, Neaples (Italy). Servizio di Radiologia); Scialpi, M. (Ospedale Civile SS. Annunziata, Taranto (Italy). Unita' Operativa di Radiodiagnostica, Sez. di Tomografia Computerizzata); Rossi, E.; Carbone, M.; Brunese, L. (Neaples Univ. Federico 2, Neaples (Italy). Ist. di Scienze Radiologiche); Nocera, V. (Ospedale A. Cardarelli, Naples (Italy). Servizio di Radiologia); Muto, M. (Azienda di Rilievo Nazionale A. Cardarelli, Neaples (Italy). Servizio di Neuroradiologia)

    Gunshot wounds to the head are usually mortal injures. Their frequency has been increasing in the last years because of increasing crime rates. Emergency Computed Tomography (CT) makes a useful tool for depicting bullet course and brain damage, and thus helps plan treatment. It has been investigated on the CT signs of subdural hematoma, lacerocontusive focus, subarachnoid hemorrhage, hemoencephalus, skull bone fracture and thecal hollow and report them as an aid to the neurosurgeon and the radiologist, for best treatment planning, and in an attempt to establish use prognostic criteria. It has been reviewed 23 cases of gunshot injuries to the head studied with CT at the Emergency Unit of Loreto Mare 2048ital in Naples, Italy. Twenty patients were men and 3 women; their mean age was 31 years (range: 18-49). Three women and 2 men had been injured accidentally by wandering bullets, and one case was an attempted suicide; all the other cases resulted from shootings. It was found 22 penetrating gunshot wounds: 13 of them with thecal entry hole and intracranial bullet retention and 9 with an entry and exit hole. One case was a superficial wound. Crash skull fractures were seen in 22 cases and they were fragmented in 12, with overlapping thecal fragments in 4, and with deep fragments in 2 cases. Gunshot wounds to the head are complex and severe traumas with high mortality rates because of both early and late effects and complications. CT provides the neurosurgeon with abundant findings for diagnosis and surgical planning, which may result in improved survival rates. In these patients emergency CT plays a fundamental diagnostic role in depicting brain damage and thus remains the method of choice for thorough, rapid and accurate brain and skull studies, as well as to detect possible injury to the chest and abdomen.

  4. Estudo comparativo do tono muscular na paralisia cerebral tetraparética em crianças com lesões predominantemente corticais ou subcorticais na tomografia computadorizada de crânio

    OpenAIRE

    Iwabe,Cristina; Piovesana,Ana Maria Sedrez Gonzaga

    2003-01-01

    OBJETIVO: Comparar a distribuição e intensidade do tono muscular na paralisia cerebral tetraparética espástica (PC-T), correlacionando os dados clínicos com a localização da lesão no sistema nervoso central. MÉTODO: Foram incluídas 12 crianças de dois a quatro anos de idade com lesões predominantemente corticais (seis crianças) e subcorticais (seis crianças). O tono foi analisado nos membros superiores (MMSS) e inferiores (MMII) baseado no protocolo de Durigon e Piemonte. RESULTADOS: Não houv...

  5. Comparison between computed tomography with oral oil-based contrast and laparotomy for gastric cancer staging; Tomografia computerizada con contraste oral graso frente a lapartomia en la estadificacion del cancer gastrico

    Energy Technology Data Exchange (ETDEWEB)

    Marco, S. F.; Garcia-Vila, J. H.; Cervera, J.; Gomez, R.; Piqueras, R. M.; Perona, I.; Escrig, J.; Salvador, J. L. [Hospital General de Castello. Castellon (Spain)

    2000-07-01

    To compare the utility of conventional computed tomography (CT) with oral oil-based contrast with that of laparotomy in the preoperative staging of gastric cancer. We prospectively studied 41 patients diagnosed as having gastric adenocarcinoma according to the results of endoscopy and biopsy. Applying the TNM classification for gastric cancer staging, we compared the findings in CT associated with oral oil-based contrast and intraoperative staging with definitive postoperative pathological staging. Definitive pathological studies demonstrated that there were 7 stage T1-T2 lesions, 26 stage T3 and 8 stage T4. The assessment of lymph node involvement showed that 10 patients presented stage N0 and 31 stage N1-N3. Ten patients had metastases. The diagnostic reliability for tumor staging according to CT was 56% versus 80% for laparotomy. In the determination of nodal involvement CT had a diagnostic yield of 71% versus 6% for laparotomy. Metastatic disease was correctly diagnosed by CT in 83% of cases versus 88% by laparotomy. There were no statistically significant differences between CT with oral oil-based contrast and laparotomy for the staging of nodal involvement and metastases. However, the CT diagnosis was significantly more reliable than laparotomy for the determination of tumor infiltration. (Author) 21 refs.

  6. Tomografia elétrica 2D e gravimetria para detecção de sítio contaminado por derivados de petróleo em área de passivo ambiental

    Directory of Open Access Journals (Sweden)

    Valter Antonio Becegato

    Full Text Available RESUMO Foram realizados ensaios geofísicos, como caminhamento elétrico (arranjo dipolo-dipolo com AB=MN=4 m, totalizando 1.024 m de perfis, e levantamento gravimétrico, totalizando 273 estações separadas de 4 em 4 m. Os valores máximos, mínimo, médio e desvio padrão da resistividade elétrica real em ohm.m foram, respectivamente: 35, 2.276, 432 e 344. Com relação às anomalias gravimétricas Bouguer, observou-se que a porção oriental é caracterizada por sinais com maiores amplitudes, em contraposição ao segmento ocidental, onde as mesmas são intermediárias a baixas, destacando-se valores mínimos entre as estações 0-44 m das linhas L4, L5 e L6. Detectou-se a presença de hidrocarboneto a 3 m de profundidade, nas linhas L8 e L9. Análises laboratoriais das amostras de solos e água apontaram valores PHAs que excedem os parâmetros estabelecidos pela resolução CONAMA nº 357/2005.

  7. Cranial computed tomography findings in patients admitted to the emergency unit of Hospital Universitario Cajuru; Achados tomograficos de pacientes submetidos a tomografia de cranio no pronto-socorro do Hospital Universitario Cajuru

    Energy Technology Data Exchange (ETDEWEB)

    Lara Filho, Lauro Aparecido; Omar, Samir Sari; Biguelini, Rodrigo Foletto; Santos, Rony Augusto de Oliveira, E-mail: samir176@gmail.com [Pontificia Universidade Catolica do Parana (PUCPR), Curitiba, PR (Brazil). Cuso de Medicina

    2013-05-15

    Objective: to identify and analyze the prevalence of cranial computed tomography findings in patients admitted to the emergency unit of Hospital Universitario Cajuru. Materials and methods: cross-sectional study analyzing 200 consecutive non contrast-enhanced cranial computed tomography reports of patients admitted to the emergency unit of Hospital Universitario Cajuru. Results: alterations were observed in 76.5% of the patients. Among them, the following findings were most frequently observed: extracranial soft tissue swelling (22%), bone fracture (16.5%), subarachnoid hemorrhage (15%), nonspecific hypodensity (14.5%), paranasal sinuses opacification (11.5%), diffuse cerebral edema (10.5%), subdural hematoma (9.5%), cerebral contusion (8.5%), hydrocephalus (8%), retractable hypodensity /gliosis/ encephalomalacia (8%). Conclusion: the authors recognize that the most common findings in emergency departments reported in the literature are similar to the ones described in the present study. This information is important for professionals to recognize the main changes to be identified at cranial computed tomography, and for future planning and hospital screening aiming at achieving efficiency and improvement in services. (author)

  8. Computed tomography of head: impact of the use of automatic exposure control; Doses em tomografia computadorizada de crânio: impacto do uso do controle automático de exposição

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    Souza, Giordana Salvi de Souza; Froner, Ana Paula Pastre; Silva, Ana Maria Marques da, E-mail: giordana.souza@acad.pucrs.br [Pontificia Universidade catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Núcleo de Pesquisa em Imagens Médicas

    2017-07-01

    The use of dose reduction systems in computed tomography is particularly important for pediatric patients, who have a high radiosensitivity, since they are in the growing phase. The aim of this study was to evaluate the impact of Siemens AEC Care Dose system use on dose estimation in head computed tomography scans in pediatric patients. A retrospective study was conducted with 199 computed tomography head scans of pediatric patients, divided in different age groups, on a 16-channel Siemens Emotion scanner. It was possible to observe, for all age groups, that the use of AEC Care Dose system, not only reduced CTDI{sub vol}, but also the interquartile range, reducing the total dose in the investigated population. Concluding, AEC Care Dose system models the tube current according to the patient's dimensions, reducing individual and collective dose without affecting the diagnostic quality . (author)

  9. Optimization of protocol in computerized tomography scans of children's chest; Otimização de protocolo em varreduras de tomografia computadorizada de tórax infantil

    Energy Technology Data Exchange (ETDEWEB)

    Lima, L.T.A.; Roberto, W. dos S.; Mourão Filho, A.P., E-mail: luanaabrao@gmail.com, E-mail: aprata@des.cefetmg.br [Centro Federal de Educação Tecnológica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Núcleo de Engenharia Hospitalar

    2017-07-01

    The diffusion of the Computed Tomography (CT) has promoted a significant increase of the dose absorbed by patients. This technique showed a high growth as a result of clinical cases of medical emergencies, neoplasia and pediatric traumas. The risks of stochastic effects are greater for children due to tissue radiosensitivity coupled with longer life expectancy. In the present work, a cylindrical simulator was used, representing an adult thorax made of polymethylmethacrylate (PMMA), and a second simulator object of the same material was developed in oblong format including the axillary regions, based on the dimensions of the patient's thorax one-year-old pediatric population. The scanning on the adult simulator object was performed with the chest radiograph diagnostic service with a 120 kV supply voltage and in the pediatric simulator object were performed optimized scans with 120, 100 and 80 kV. This work compared the dose variation absorbed by the pediatric simulator object mentioned by the change in the tube supply voltage.

  10. Optimization of recommendations for abdomen computerized tomography based on reconstruction filters, voltage and tube current; Otimizacao de protocolos de tomografia computadorizada de abdome com base nos filtros de reconstrucao, tensao e corrente do tubo

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, Vinicius da Costa

    2015-07-01

    The use of computed tomography has increased significantly over the past decades. In Brazil the use increased more than twofold from 2008 to 2014, in the meantime the abdomen procedures have tripled. The high frequency of this procedure combined by the increasing collective radiation dose in medical exposures, has resulted development tools to maximize the benefit in CT images. This work aimed to establish protocols optimized in abdominal CT through acquisitions parameters and reconstructions techniques based on filters kernels. A sample of patients undergoing abdominal CT in a diagnostic center of Rio de Janeiro was assessed. Had been collected patients information and acquisitions parameters. The phantoms CT image acquisitions were performed by using different voltage values by adjusting the tube current (mAs) to obtain the same value from CTDI{sub vol} patients with normal BMI. Afterwards, the CTDIvol values were reduced by 30%, 50% and 60%. All images were reconstructed with low-contrast filters (A) and standard filters (B). The CTDIvol values for patients with normal BMI were 7% higher than in patients with underweight BMI and 30%, 50% and 60% lower than the overweight, obese I and III patients, respectively. The evaluations of image quality showed that variation of the current (mA) and the reconstruction filters did not affect the Hounsfield values. When the contrast-to-noise ratio (CNR) was normalized to CTDIvol, the protocols acquired with 60% reduction of CTDIvol with 140 kV and 80 kV showed CNR 6% lower than the routine. Modifications of the acquisition parameters did not affect spatial resolution, but the post-processing with B filters reduced the spatial frequency by 16%. With reduced the dose of 30%, lesions in the spleen had the CNR higher than 10% routine protocols with 140 kV acquired and post-processed to filter A. The image post-processing with a filter A with a 80kV voltage provided CNR values equal to the routine for the liver lesions with a 30% reduction in dose. This study demonstrated that the reduction in tube voltage and the image post-processing filter to enable a reduction in the radiation dose by 30%. (author)

  11. Computed tomography in Brazil: frequency and pattern of usage among inpatients of the Unified Health System (SUS); Tomografia computadorizada no Brasil: frequencia e padrao de uso em pacientes internados no Sistema Unico de Saude (SUS)

    Energy Technology Data Exchange (ETDEWEB)

    Dovales, Ana Cristina M.; Souza, Andressa A. de; Veiga, Lene H.S., E-mail: adovales@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-04-15

    This paper shows the frequency, pattern and trend of computed tomography use in inpatients of the Brazilian public health care system (SUS), from 2008 to 2011. Data were extracted from an Internet database provided by SUS. Head/neck examinations were the most frequent type of CT over the study period. The use of CT increased over time, with the greatest increase being observed for CT of extremities. (author)

  12. Optimization of the dose versus noise in the image on protocols for computed tomography of pediatric head;Otimizacao da relacao dose versus ruido na imagem em protocolos de tomografia computadorizada de cranio pediatrico

    Energy Technology Data Exchange (ETDEWEB)

    Saint' Yves, T.L.A.; Travassos, P.C.; Goncalves, E.A.S.; Mecca, F.A.; Silveira, T.B. [Instituto Nacional de Cancer (INCA), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    This article aims to establish protocols optimized for computed tomography of pediatric skull, to the Picker Q 2000 tomography of the Instituto Nacional de Cancer, through the analysis of dose x noise on the image with the variation of values of m As and k Vp. We used a water phantom to measure the noise, a pencil type ionization chamber to measure the dose in the air and the Alderson Randon phantom for check the quality of the image. We found values of m As and k Vp that reduce the skin dose of the original protocol used in 35.9%, maintaining the same image quality at a safe diagnosis. (author)

  13. Optimization on the dose versus noise in the image on protocols for computed tomography of pediatric head; Otimizacao da relacao dose versus ruido na imagem em protocolos de tomografia computadorizada de cranio pediatrico

    Energy Technology Data Exchange (ETDEWEB)

    Saint' Yves, Thalis L.A.; Travassos, Paulo Cesar B.; Goncalves, Elicardo A.S.; Mecca A, Fernando; Silveira, Thiago B. [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil)], e-mail: fmecca@inca.gov.br, e-mail: thalis09@yahoo.com.br

    2010-03-15

    This article aims to establish protocols optimized for computed tomography of pediatric skull, to the Picker Q2000 tomography of the Instituto Nacional de Cancer, through the analysis of dose x noise on the image with the variation of values of mAs and kVp. We used a water phantom to measure the noise, a pencil type ionization chamber to measure the dose in the air and the Alderson Randon phantom for check the quality of the image. We found values of mAs and kVp that reduce the skin dose of the original protocol used in 35.9%, maintaining the same image quality at a safe diagnosis. (author)

  14. Retrospective study of ear findings of dogs submitted to cranial tomography in FMVZ - UNESP, Botucatu; Estudo retrospectivo dos achados otologicos de caes submetidos a tomografia craniana na FMVZ - UNESP, Botucatu

    Energy Technology Data Exchange (ETDEWEB)

    Babicsak, Viviam Rocco; Oliveira, Hugo Salvador de; Belotta, Alexandra Frey; Santos, Debora Rodrigues dos; Zardo, Karen Maciel; Mamprim, Maria Jaqueline; Machado, Vania Maria de Vasconcelos; Vulcano, Luiz Carlos, E-mail: viviam.babicsak@gmail.com [Universidade Estadual Paulista Julio de Mesquita Filho (FMVZ/UNESP), Botucatu, SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia. Dept. de Reproducao Animal e Radiologia Veterinaria

    2012-07-01

    Computed tomography (CT) is an important imaging modality in the diagnosis of ear alterations, especially those affecting the middle ear. In this retrospective study, in which the cranial CT scans of 151 dogs were evaluated, the most common finding was the mineralization of the external auditory cartilage, followed by secretions in external and middle ear and tissue in these two regions. The average age of affected animals ranged from 6-9 years. Mixed breed dogs were the most affected animals, followed by cockers, boxers, poodles, labrador retrievers, german shepherds and pit bulls. (author)

  15. The diagnostic contribution of computed tomography in intranasal carcinoma with retrobulbar, oral and brain invasion in a canine: case report; Contribuicao da tomografia computadorizada no diagnostico de carcinoma intranasal com invasao retrobular, oral e cerebral em canino: relato de caso

    Energy Technology Data Exchange (ETDEWEB)

    Zardo, Karen Maciel, E-mail: kmz@bol.com.br; Belotta, Alexandra Frey; Babicsak, Viviam Rocco; Machado, Vania Maria de Vasconcelos [Universidade Estadual Paulista Julio de Mesquita Filho (FMVZ/UNESP), Botucatu, SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia. Dept. de Reproducao Animal e Radiologia Veterinaria; Zanoni, Diogo Souza; Costa, Denis Carvalho [Universidade Estadual Paulista Julio de Mesquita Filho (FMVZ/UNESP), Botucatu, SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia. Dept. de Clinica Veterinaria

    2012-07-01

    Intranasal tumors are uncommon and in most cases are malignant, aggressive and with low to moderate potential for metastasis. Clinical signs are usually caused by progressive obstruction of the upper airways. The test cytopathological also is a diagnosis method, but the definitive diagnosis is made by histopathological. Computed tomography (CT) is recommended to treatment planning. A poodle was attended at the veterinary hospital with a clinical history of epistaxis and nasal and ocular secretions, seizures and severe dyspnoea. The animal underwent to radiographic examination of the chest and skull as well as helical computed tomography of the nasal cavity and brain before and after the administration of intravenous contrast. The CT findings revealed an expansive bilateral nasal cavity neoformation, with involvement of the retrobulbar space, right frontal sinus, brain and oral cavity, suggesting a neoplastic or an infectious process. The CT examination allowed the material collection, directly from the mass, to cytological examination, providing the diagnosis of carcinoma. CT also allowed the determination of the unfavorable prognosis of the patient and the treatment planning which not included the surgical excision of the neoformation. Although CT was not conclusive in the diagnosis of carcinoma, it was essential to accurately define the extent of the lesion, to guide the collection of material directly from the tumor and to determine the prognosis of the animal, proving to be an extremely useful tool in cases of tumors intranasal in dogs. (author)

  16. Prevalence of brain atrophy in dogs submitted to cranial tomography in FMVZ - UNESP Botucatu: retrospective study; Prevalencia de atrofia cerebral em caes submetidos a tomografia craniana na FMVZ - UNESP Botucatu: estudo retrospectivo

    Energy Technology Data Exchange (ETDEWEB)

    Babicsak, Viviam Rocco; Belotta, Alexandra Frey; Oliveira, Hugo Salvador de; Zardo, Karen Maciel; Santos, Debora Rodrigues dos; Mamprim, Maria Jaqueline; Machado, Vania Maria de Vasconcelos; Vulcano, Luiz Carlos, E-mail: viviam.babicsak@gmail.com [Universidade Estadual Paulista Julio de Mesquita Filho (FMVZ/UNESP), Botucatu, SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia . Dept. de Reproducao Animal e Radiologia Veterinaria

    2012-07-01

    Brain atrophy is diagnosed by imaging methods that allow the verification of the widening of cerebral sulci and ventricular dilatation. In this retrospective study, in which the cranial CT scans of 150 dogs were evaluated, brain atrophy was identified in 16 animals. Mixed breed dogs were the most affected, followed by poodles, maltese, dachshunds, yorkshires, pinschers and cockers. Brain atrophy was observed in animals of all age groups, being more prevalent in middle aged dogs followed by elderly animals, in which this alteration can be commonly found. The identification of reduced brain volume, however, may not be the cause of neurological signs expressed by animals since in some dogs of this study it was considered a finding. (author)

  17. Tomografia computadorizada de feixe cônico como método de avaliação pós-tratamento endodôntico em sessão única ou em duas sessões

    OpenAIRE

    Claudia de Castro Rizzi Maia

    2014-01-01

    Resumo Introdução: Estudos epidemiológicos reportam elevada prevalência de lesão periapical em diferentes países, concluindo que esta constitui um problema de saúde que afeta grande parte da população. Proposição: O objetivo deste estudo clínico randomizado foi efetuar uma avaliação comparativa pós-tratamento endodôntico de dentes permanentes com lesão periapical crônica, realizado em sessão única ou em duas sessões com o uso de hidróxido de cálcio, por 14 dias, como curativo de demora entre ...

  18. Optimization of protocols and increase the life of the tube of X rays in computer tomography;Otimizacao de protocolos e aumento dsa vida util do tubo de raios X em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Viero, A.P. [Centro Universitario Franciscano, Santa Maria, RS (Brazil); Botelho, Marcel Z.; Torunsky, Caroline G. [STAFF - Solucoes em Fisica Medica e Radioprotecao, Santa Maria, RS (Brazil); Paula, V. [Clinica Radiologica Caridade (DIX), Santa Maria, RS (Brazil)

    2009-07-01

    The objective of this study was to evaluate the reduction of the radiation dose and X-ray tube heating in computed tomography exams. Exams of the skull, abdomen and thorax were evaluated. It was verified that the technique used could be changed, suggesting new protocols and comparing image quality, radiation dose and X-ray tube heating. A mAs reduction could be done without compromising the diagnostic quality bringing a decrease up to 21,92% in the dose of skull exams, 20,25% for the examinations, abdomen and 22,06% for the examinations of thorax. The reduction on the X-ray tube heating for skull, abdomen and thorax exams was approximately 22,2%, 20,0% and 22,2% respectively. It is concluded that a change on the described protocols will cause a significant reduction dose delivered to patients and on X-ray tube heating without compromising the diagnosis. (author)

  19. Computed tomography prospective study of pleural-pulmonary changes after abdominal surgery : assessment of associated risk factors; Estudo prospectivo por tomografia computadorizada das alteracoes pleuro-pulmonares apos cirurgia abdominal: avaliacao dos fatores de risco associados

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Luis Antonio [Pontificia Univ. Catolica de Sao Paulo, SP (Brazil). Centro de Ciencias Medicas e Biologicas]. E-mail: luizrossimd@uol.com.br; Bromberg, Sansom Henrique [Instituto de Assistencia Medica ao Servidor Publico Estadual de Sao Paulo (IAMSPE), Sao Paulo, SP (Brazil). Curso de Pos-graduacao em Gastroenterologia Cirurgica

    2005-07-01

    Postoperative pleural-pulmonary changes (PPC) are very common following elective abdominal surgery, resolving without clinical manifestations in most patients. The incidence and risk factors associated are unknown. Objective: to determine the incidence of PPC and possible association with risk factors using computerized tomography (CT). Material and method: thirty seven patients submitted to elective abdominal surgery were prospectively analyzed using CT performed in the preoperative period and 48 hours after surgery. The PPC was scored from 0 to III. The risk factors evaluated were: age, sex, obesity, smoking history, alcoholism, comorbid conditions, cancer, ASA classification, duration of surgery, surgical incision type and number of days of hospitalization. Results: Pleura effusion was detected by CT in 70.3% (26/37) of the patients and pulmonary atelectasis in 75.5% (28/37). Grade I and II PPC was found in 59.5% (22/37) of the patients and grade III in 21.6% (8/37). Two (5.4%) of these patients developed serious pulmonary complications whereas one patient died. Surgery due to cancer, class ASA >2, longitudinal incision and > 15 cm showed statistical significance and were associated with pleural effusion. The hospitalization was over 2.4 longer for patients with PPC. Conclusion: PPC is frequently seen in patients submitted to abdominal surgery. The use of the CT for the detection of pulmonary atelectasis and pleural effusion proved to be effective. Most cases of PPC are self-limited, resolving without symptoms. (author)

  20. Seeking tools for image fusion between computed tomography, structural and functional magnetic resonance methods for applications in neurosurgery; Ferramentas para fusao de imagens dos metodos de tomografia computadorizada, ressonancia magnetica e ressonancia magnetica funcional para aplicacao pre-neurocirurgica

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Liana Guerra Sanches da, E-mail: liana@einstein.br [Departamento de Diagnostico por Imagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo (SP) (Brazil); Amaro Junior, Edson [Faculdade de Medicina, Universidade de Sao Paulo - USP, Sao Paulo, SP (Brazil). Deptartamento de Diagnostico por Imagem; Instituto do Cerebro - InCe, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil)

    2012-04-15

    To evaluate tools for the fusion of images generated by tomography and structural and functional magnetic resonance imaging. Methods: Magnetic resonance and functional magnetic resonance imaging were performed while a volunteer who had previously undergone cranial tomography performed motor and somatosensory tasks in a 3-Tesla scanner. Image data were analyzed with different programs, and the results were compared. Results: We constructed a flow chart of computational processes that allowed measurement of the spatial congruence between the methods. There was no single computational tool that contained the entire set of functions necessary to achieve the goal. Conclusion: The fusion of the images from the three methods proved to be feasible with the use of four free-access software programs (OsiriX, Register, MRIcro and FSL). Our results may serve as a basis for building software that will be useful as a virtual tool prior to neurosurgery. (author)

  1. Analysis of absorbed dose in cervical spine scanning by computerized tomography using simulator objects; Análise de dose absorvida em varreduras de coluna cervical por tomografia computadorizada utlizando objetos simuladores

    Energy Technology Data Exchange (ETDEWEB)

    Lyra, Maria Henriqueta Freire

    2015-07-01

    The Computed tomography (CT) has become an important diagnostic tool after the continued development of Multidetector CT (MDCT), which allows faster acquisition of images with better quality than the previous technology. However, there is an increased radiation exposure, especially in examinations that require more than one acquisition, as dynamic exams and enhancement studies in order to discriminate low contrast soft tissue injury from normal tissue. Cervical spine MDCT examinations are used for diagnosis of soft tissue and vascular changes, fractures, dysplasia and other diseases with instability, which guide the patient treatment and rehabilitation. This study aims at checking the absorbed dose range in the thyroid and other organs during MDCT scan of cervical spine, with and without bismuth thyroid shield. In this experiment a cervical spine MDCT scan was performed on anthropomorphic phantoms, from the occipital to the first thoracic vertebra, using a 64 and a 16 – channel CT scanners. Thermoluminescent dosimeters were used to obtain the absorbed dose in thyroid, lenses, magnum foramen and breasts of the phantom. The results show that the thyroid received the highest dose, 60.0 mGy, in the female phantom, according to the incidence of the primary X-ray beam. The absorbed doses in these tests showed significant differences in the evaluated organs, p value < 0.005, except for the magnum foramen and breasts. With the bismuth thyroid shield applied on the female phantom, the doses in the thyroid and in the lenses were reduced by 27% and 52%, respectively. On the other hand, a reduction of 23.3% in the thyroid and increasing of 49.0% in the lens were measured on the male phantom. (author)

  2. Dysgenesis of the corpus callosum and associated malformaaation{sup :} computed tomography and magnetic resonance imaging findings; Disgenesia do corpo caloso e mas-formacoes associadas: achados de tomografia computadorizada e ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Montandon, Cristiano; Montandon Junior, Marcelo Eustaquio [Colegio Brasileiro de Radiologia e Diagnostico por Imagem (CBR), Sao Paulo, SP (Brazil); Ribeiro, Flavia Aparecida de Sousa; Lobo, Leonardo Valadares Barbosa; Teixeira, Kim-Ir-Sen Santos [Goias Univ., Goiania (Brazil). Hospital de Clinicas. Dept. de Diagnostico por Imagem e Anatomia Patologica]. E-mail: cabeca2@terra.com.br

    2003-10-01

    Callosal dysgenesis is a malformation of the corpus callosum with origins in the embryogenesis of the telencephalon. We reviewed the computed tomography and magnetic resonance imaging findings of 11 patients with callosal dysgenesis and one patient with normal corpus callosum associated with a lipoma. The patients were divided into three distinct groups: total agenesis (three patients), partial agenesis (six patients) and hypoplasia (two patients). Associated abnormalities were observed in nine patients, including Chiari II malformation (one patient), schizencephaly (one patient), interhemispheric cyst (two patients), Dandy-Walker cyst (one patient), nodular heterotopy (one patient) and lipoma of the corpus callosum (four patients). This paper presents a review that may contribute to the diagnosis of these disorders. (author)

  3. CT Assessment of the axial deviation of the femoral and tibial prosthetic components in total knee arthroplasty; Valutazione con Tomografia Computerizzata della rotazione delle componenti femorale e tibiale nell'artroprotesi totale del ginocchio

    Energy Technology Data Exchange (ETDEWEB)

    Rimondi, E.; Molinari, M.; Moio, A.; Busacca, M. [Istituto Ortopedico Rizzoli, Bologna (Italy). Servizio di Diagnostica per Immagini; Trentani, F.; Trentani, P.; Tigani, D. [Istituto Ortopedico Rizzoli, Bologna (Italy). VII Div.; Nigrosoli, M. [Istituto Ortopedico Rizzoli, Bologna (Italy). IV Div.

    2000-06-01

    CT assessment of the axial deviation of the femoral and tibial prosthetic components in total knee arthroplasty. From January to July 1999, 17 patients, 10 males and 7 females, mean age 66 years (standard deviation plus or minus 4) were examined after total knee arthroplasty. Exclusion criteria were prosthesis loosening and severe (equal or superior to 7 degrees) varus o valgus deviation. All patients were examined with knee radiography in the standing position completed by axial projection of patella and by CT scanning. It was used a modification of Berger technique and carried out comparative CT scans extended lower limbs and acquisitions perpendicular to the mechanical axis of the knee, from the femoral supracondylar region down to the plane crossing the distal end of the tibial prosthetic component. Reference lines were then drawn electronically on given scanning planes to reckon the axial deviation of the femoral and tibial prosthetic components. Six patients, one female and 5 males with normal rotational values of femoral and tibial prosthetic components presented no clinical symptoms. Eight patients, 4 females and 4 males, with abnormal values presented the following clinical symptoms: medial impingement, (incomplete) dislocation patella, and lateral instability. One female patient with a normal rotational value of femoral prosthetic component and an altered value of tibial prosthetic component presented medial impingement. Finally two patients, one female and one male, were absolutely asymptomatic although the rotational values of the two prosthetic components were beyond the normal range. Total knee arthroplasty is presently a standard treatment for many conditions involving this joint. There are several possible postoperative complications, namely fractures, dislocations (a)septic losening and femoropatellar instability. The latter condition is the most frequent complication among implant failures and is caused by bad orientation of the femoral and tibial components on frontal and axial planes. It was measured the orientation of the prosthetic components introducing a CT procedure which modifies the uniarticular with four scans introduced by Berger. The new method uses Berger's parameters and the CT study of both joints by means of Helical CT. With a single examination lasting less than 4 minutes and with the patient in a more confortable position, it can be obtained: (1) comparative and simultaneous assessment of the contralateral joint; (2) several scans to better define Berger's parameters and to accomplish measurement of the rotational deviation with higher precision and markedly decreasing the error margin. The analysis of the results confirms the international literature findings and especially the fundamental importance in positioning both prosthetic components within normal values, as emphasized by the relationship between the clinical symptoms and the rotational degree of the femoral and tibial prosthetic components. [Italian] Scopo di questo lavoro e' valutare mediante TC la rotazione delle componenti protesiche femorale e tibiale nella protesi del ginocchio. Da gennaio a luglio 1999 sono stati esaminati 17 pazienti, 10 maschi e 7 femmine, eta' media 66 anni (deviazione standard plus minus 4) operati di protesi totale del ginocchio. Sono stati esclusi tutti i soggetti con mobilizzazione delle componenti protesiche e con deviazioni gravi (uguali o superiore a 7) nel varismo o nel valgismo. Ogni paziente e' stato studiato con radiogrammi del ginocchio nell'ortostasi in due proiezioni completate da assiali della rotula e mediante TC. Rispetto alla metodica descritta da Berger la TC e' stata efettuata comparativamente con arti inferiori estesi scansioni perpendicolari all'asse meccanico del ginocchio, condotte dalla regione sovracondiloidea femorale al piano passante al di sotto delle estremita' distale della componente protesica tibiale. Su piani di scansione predefiniti sono poi state tracciate eletronicamente linee di riferimento per la valutazione delle deviazioni assiali delle componenti protesiche femorale e tibiale. Sei pazienti, una femmina e 5 maschi, con valori della rotazione delle componenti protesiche femorale e tibiale normali, non presentavano alcuna sintomatologia clinica. Otto pazienti, 4 femmine e 4 maschi, con valori patologici della rotazione delle componenti protesiche femorale e tibiale normali, presentavano la seguente sintomatologia clinica: conflitto mediale, sublussazione della rotula, lussazione della rotula e instabilita' laterale. Una femmina con valore di rotazione normale per la componente protesica femorale e alterato per quella tibiale presentava conflitto mediale. Infine due pazienti, una femmina e un maschio, erano assolutamente asintomatici pur con valori della rotazione delle due componenti protesiche patologici. La protesi totale di ginocchio e' oggi il trattamento abituale per diverse affezioni che colpiscono l'articolazione.(abstract truncated)

  4. Detecció d'estructures estàtiques en el cos humà usant mètodes multifreqüència en Tomografia de impedància elèctrica

    OpenAIRE

    Riu Costa, Pere Joan

    1991-01-01

    Se analiza la obtención de imágenes que representan la estructura de secciones del cuerpo humano por medio de la medida de impedancia eléctrica. El método propuesto se basa en el comportamiento frecuencial de la conductividad y permitividad de los tejidos biológicos.Para la obtención de las estructuras estáticas, y la diferenciación de los tejidos, se opta por la medida de impedancia eléctrica a diversas frecuencias. En una primera parte se demuestra la viabilidad del método propuesto basándo...

  5. Avaliação morfológica e morfométrica da articulação umerorradioulnar em cães através de exames radiográficos e por tomografia computadorizada

    Directory of Open Access Journals (Sweden)

    Alessandra Sendyk-Grunkraut

    Full Text Available RESUMO: Este estudo teve como objetivo apresentar de forma detalhada dados morfológicos e morfométricos da articulação umerorradioulnar de cães de raça definida avaliados por meio de exames físicos, radiográficos e tomográficos. A amostra dessa pesquisa constituiu-se de 44 cotovelos de cães com idades variadas. Para análise de informações obtidas, o coeficiente kappa e de correlação interclasse e associação foram realizados. Constatou-se que o desempenho individual de cada projeção radiográfica teve pobre concordância com o exame tomográfico; não houve concordância entre os observadores para as mensurações do ângulo da incisura ulnar ao exame radiográfico e tomográfico. Porém houve boa/moderada concordância para mensuração da incongruência radioulnar no plano sagital entre os observadores. Concluiu-se que nenhuma das cinco incidências radiográficas foi superior para análise radiográfica, uma vez que cada projeção apresentou melhor identificação de um compartimento do cotovelo. Medidas ao exame tomográfico para incongruência radioulnar não apresentaram reprodutibilidade no plano de reconstrução frontal, entretanto no corte sagital apresentaram boa e moderada concordância entre os observadores e que a mensuração do ângulo da incisura ulnar não apresentou repetibilidade ao exame radiográfico e nem reprodutibilidade ao exame tomográfico. Esses resultados contribuem para melhor utilização de cada exame de acordo com a região a ser avaliada bem como ressaltam a necessidade da somatória de múltiplos exames de imagem para a correta avaliação desta afecção.

  6. Cardiac tamponade in an infant during contrast infusion through central venous catheter for chest computed tomography; Tamponamento cardiaco durante infusao de contraste em acesso venoso central para realizacao de tomografia computadorizada do torax em lactente

    Energy Technology Data Exchange (ETDEWEB)

    Daud, Danilo Felix; Campos, Marcos Menezes Freitas de; Fleury Neto, Augusto de Padua [Hospital Geral de Palmas, TO (Brazil)

    2013-11-15

    Complications from central venous catheterization include infectious conditions, pneumothorax, hemothorax and venous thrombosis. Pericardial effusion with cardiac tamponade hardly occurs, and in infants is generally caused by umbilical catheterization. The authors describe the case of cardiac tamponade occurred in an infant during chest computed tomography with contrast infusion through a central venous catheter inserted into the right internal jugular vein. (author)

  7. The role of 3D Helical CT in the reconstructive treatment of maxillofacial cancers; Tomografia Computerizzata spirale con elaborazioni tridimensionali di superficie nel trattamento ricostruttivo dei tumori maligni del massiccio facciale

    Energy Technology Data Exchange (ETDEWEB)

    De Rosa, V.; Ziviello, M. [Ospedale Cardarelli, Servizio di Radiodiagnostica, Naples (Italy); Ionna, F.; Mozzillo, N. [Ospedale Cardarelli, Div. di Chirurgia B, Ist. Nazionale Tumori Fondazione G. Pascale, Naples (Italy); Parascandolo, S. [Ospedale Cardarelli, Div. di Chirurgia Maxillo-Facciale, Naples (Italy)

    2000-12-01

    Purpose of this work is to investigate the role of Helical CT and the usefulness of three-dimensional (3D) imaging for pre-operative planning and follow-up of reconstructive maxillofacial surgery with alloplastic material in neoplastic disease involving this region. From 1996 to 1999 eleven patients were examined with Helical CT and 3D images for planning of maxillofacial plastic and reconstructive surgery for advanced cancer of this anatomically complex region. A 3D-modulated titanium mesh (100%) or micronets was used to rebuild the anterior surface of maxillary bone and the orbital floor. The mesh was cut to the appropriate size and shape and curved where necessary. Within the residual sinusal cavity a siliconed filling was used surmounting an acrylic prosthesis with dental arch to rebuild the palate. A rehydrated bovine pericardium was affixed and moduled on the borders in two cases only. Three-dimensionally reconstructed CT images were obtained preoperatively and at least 6 months postoperatively in all patients. The images were generated on a computer workstation using the shaded surface display (SSD) software with threshold values ranging 425 to 630 HU, and a more closed window for the imaging of titanium mesh/bone interface in the post surgical follow-up. It was obtained an excellent complete spatial depiction of maxillo facial region both before and after surgery, with no artefacts so important as to affect the 3D reconstruction process and the image quality. Together with the head-neck surgical team it could be worked for preoperative planning through CT scans by different 3D points of view. The 3D reconstructed follow-up scans showed good filling of the defect in the area where the titanium mesh had been used. Then efficacious bone modelling and good biocompatibility of the alloplastic material were seen in all patients, with no inflammatory reactions. Titanium is a well-known material, which is widely used for cranioplasty. It is a radiolucent, non-ferrous metal of low atomic number that allows very clear CT and MR images to be obtained. Further Ti features are strength, biocompatibility and easy handling. 3D Helical CT scan has proven to be the most complete and accurate imaging technique for reconstructive plastic surgery with alloplastic material in advanced maxillofacial cancer, also considering the anatomic and functional complexity of his area. The prospect is provided to identify virtual 3D presurgical ablation planes. These may allow the surgeon to improve plastic reconstruction and shorten intervention time. [Italian] Scopo di questo articolo e' quello di analizzare il ruolo della TC spirale e i vantaggi delle ricostruzioni tridimensionali di superficie nella pianificazione e controllo degli interventi di chirurgia ricostruttiva plastica con materiale alloplastico nelle neoplasie maligne del massiccio facciale. Sono state eseguite dal 1996 al 1999 11 ricostruzioni plastiche dell'osso mascellare per neoplasie osteodestruenti il massiccio facciale utilizzando materiale alloplastico. Per la ricostruzione della parete anteriore dell'osso mascellare e del pavimento orbitario e' stata utlizzata una rete di titanio al 100% modulabile. Applicato nel cavo residuo dell'osso un otturatore siliconato sormontante una protesi acrilica con arcata dentaria per la ricostruzione del palato. In due casi utilizzato pericardio bovino modulato sulla soluzione di continuo. Tutti i pazienti sono stati studiati con TC spirale sia nella fase preoperatoria che entro il sesto mese dall'intervento chirurgico. Elaborate ricostruzioni tridimensionali della superficie (shaed surface display-SSD) con valori soglia compresi tra 425 e 630 UH ma con intervallo piu' stretto di finestra sui valori UH all'interfaccia osso/rete di titanio nei controlli del modellamento protesico. L'elaborazione tridimensionale della superificie sui dati ottenuti con acquisizione volumetrica ha fornito in tutti casi la fedele rappresentazione spaziale nella pre e post-ricostruzione dell'area chirurgica e successivamente sono stati valutati il grado del rimodellamento osseo e la buona osteointegrazione del materiale protesico. La scelta di valori soglia con finestra piu' stretta all'interfaccia osso/materiale alloplastico ha consentito la pressoche' totale eliminazione di artefatti nel processo ricostruttivo delle immagini del controllo post-chirurgico. Il titanio, sagomato in rete con unico o doppio strato, si e' dimostrato il miglior materiale per consistenza, biocompatibilita' e facile modulabilita' ed e' risultato per la sua densitometria quello meglio rappresentato nelle immagini TC. L'acquisizione volumetrica delle immagini con visioni proiettive tridimensionali e' da ritenersi indispensabile per ogni malattia del distretto maxillo-facciale che richieda ampie ricostruzioni plastiche della superficie non per aumento del contenuto informativo di base ma per la superiore valutazione spaziale della complessita' anatomica(abstract truncated)

  8. Elementary representative sizes of soil attributes via attenuation of gamma rays and computerized tomography; Tamanhos elementares representativos de atributos do solo via atenuacao de raios gama e tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Jaqueline Aparecida Ribaski

    2015-07-01

    In this study, the Computed Tomography (CT) and gamma-ray attenuation (GRA) techniques were used in the investigation of representative sample sizes for attributes related to soil structure. First of all, the representative elementary length (REL) for experimental measurements of soil mass attenuation coefficient (μes), of samples from a sandy and a clayey soil, was analyzed. The study was conducted with two radioactive sources ({sup 241}Am and {sup 137}Cs), three collimators (2 - 4 mm diameters), and 14 thickness (x) samples (2-5 cm). From these analyzes, it was possible to identify an ideal thickness range for each of the studied sources (2-4 cm and 12-15 cm for the sources of {sup 241}Am and {sup 137}Cs, respectively). The application of such results in representative elementary area evaluations, in clayey soil clods via CT, indicated that experimental soil mass attenuation coefficient average values obtained for x>4 cm and source {sup 241}Am might induce the use of samples which are not large enough for soil bulk density evaluations. Subsequently, μCT images with a total volume of 39×39×33 mm{sup 3} and spatial resolution of 60 μm were used for macroporous system morphological characterization of a Rhodic Ferralsol with clayey texture, under no-till (NT) and conventional till (CT) systems. Attributes as macroporosity (MAP), number of macropores (NMAP), tortuosity (τ) and connectivity (C) of the pores were assessed. The C degree was estimated based on the Euler-Poincare characteristic (EPC). Once 3D images enable the study of these attributes in different sample volumes, the proposed study is ideal for the analysis of representative elementary volume (REV). Usually, the selection of subvolumes for REV analysis occurs concentrically to a small volume or in adjacent positions. Here, we introduced a new method for selecting the positions of subvolumes, which are randomly chosen within the total image volume (random selection). It was observed that higher fluctuations in amplitude of each analyzed property values occurred for smaller subvolumes and random selection. When these positions are randomly selected, all regions of the sample have the same probability of occurrence. Thus, the subvolumes can be selected from regions that exhibit similar characteristics, or which are quite different from each other. The results allowed the study of each of these attributes in function of the analyzed sample volume. Such analysis enabled the identification of a REV for MAP and τ measurements for both soils. However, NMAP and CEP showed no indication of stabilization within the total sample volume analyzed (39×39×33 mm{sup 3}). From this study, it was possible to detect the influence of each management systems (NT and CT) on the macroporous system. In general, results obtained for soil under PC showed higher regularity, which is probably due to its homogenization induced by the plowing, conducted twice a year. (author)

  9. New developments in molecular imaging: positron emission tomography time-of-flight (TOF-PET); Nuevos desarrollos en imagen molecular: Tomografia por Emision de Positrones con Teimpo de Vuelo (TOF-PET)

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar, P.; Couce, B.; Iglesias, A.; Lois, C.

    2011-07-01

    Positron Emission tomography (PET) in increasingly being used in oncology for the diagnosis and staging of disease, as well as in monitoring response to therapy. One of the last advances in PET is the incorporation of Time-of-Flight (TOF) information, which improves the tomographic reconstruction process and subsequently the quality of the final image. In this work, we explain the principles of PET and the fundamentals of TOF-PET. Clinical images are shown in order to illustrate how TOF-PET improves the detectability of small lesions, particularly in patients with high body mass index. (Author) 20 refs.

  10. Radiological protection for multislice computed tomography in pregnant women in the supplementary diagnosis of fetal Thanatophoric dysplasia; Cuidados com protecao radiologica durante tomografia computadorizada multslice em gestante no diagnostico complementar de displasia tanatoforica fetal

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Jose Thiago de Souza de; Lima, Rogerio Aparecido; Ferreira, Josias dos Santos, E-mail: jthiagoc@hc.unicamp.br, E-mail: rxroger@hc.unicamp.br, E-mail: josiasrx@hotmail.com [Universidade Estadual de Campinas (HC/UNICAMP), SP (Brazil). Hospital de Clinicas. Dept. de Radiologia

    2014-07-01

    Thanatophoric Dysplasia is a rare genetic disorder that leads to the normal growth of the individual leaving him with short stature deterrent. Patients with this syndrome have disproportionately short limbs, with extra skin folds, narrowing chest, small ribs, underdeveloped lungs and hydrocephalus. The Thanatophoric Dysplasia can be diagnosed by ultrasonography (US), with approximately 23 weeks of gestation. If there is suspicion of a lethal skeletal dysplasia CT with 3D reconstruction can be suggested. In the use of CT Multslice 3D for prenatal diagnosis of Thanatophoric Dysplasia, one should take into account the radiation dose. To reduce the radiation dose in the pregnant woman and her fetus, it is possible to employ a chain of smaller pipe without compromising the picture quality through automatic exposure control (AEC) which is based on the principle of CT Multslice. AEC Such systems are designed to adjust the tube current according to the patients shape, size, and attenuation of X-rays. One study compared the use of 2D-US and 3D-CT completion is lower cost and the absence of radiation in the US, the method is dependent on the volume of amniotic fluid and fetal position. The 3D-CT can demonstrate all fetal skeleton. The 2D US provided correct diagnosis in four of the six cases studied, while 3D-CT yielded the correct diagnosis in all six cases. (author)

  11. Study of ionizing radiation effects in human costal cartilage by thermogravimetry and optical coherence tomography; Estudo dos efeitos da radiacao ionizante em cartilagem costal humana por meio de termogravimetria e tomografia por coerencia optica

    Energy Technology Data Exchange (ETDEWEB)

    Martinho Junior, Antonio Carlos

    2012-07-01

    Tissue Banks around the world have stored human cartilages obtained from post mortem donors for use in several kinds of reconstructive surgeries. To ensure that such tissues are not contaminated, they have been sterilized with ionizing radiation. However, high doses of gamma radiation may cause undesirable changes in the tissues. In this work, we evaluated the possibility of use Optical Coherence Tomography (OCT) and Thermogravimetric Analysis (TGA) to identify possible structural modifications caused by both preservation methods of cartilage and gamma irradiation doses. Cartilages were obtained from cadaveric donors and were frozen at -70 deg C or preserved in glycerol. Irradiation was performed by {sup 60}Co source with doses of 15, 25 and 50 kGy. Our TGA results showed that glycerolized cartilages irradiated with different doses of radiation does not presented statistical differences when compared to the control group for the dehydration rate. However, the same was not observed for deep-frozen cartilages irradiated with 15 kGy. The results of OCT associated to total optical attenuation coefficient showed that doses of 15 kGy promote cross-link between collagen fibrils, corroborating the results obtained from TGA. Moreover, total optical attenuation coefficient values are proportional to stress at break of cartilages, what will be very useful in a near future to predict the quality of the allografts, without unnecessary loss of biological tissue, once OCT is a nondestructive technique. By PS-OCT images, we found that high doses of ionizing radiation does not promote sufficient impairments to promote complete loss of tissue birefringence. Thus, TGA and OCT are techniques that can be used for tissue banks to verify tissue quality before its transplant. (author)

  12. Computed tomography findings in closed obstruction of the small bowel associated with rupture of the cecum - a case report; Obstrucao em alca fechada com ruptura do ceco: aspectos na tomografia computadorizada - relato de um caso

    Energy Technology Data Exchange (ETDEWEB)

    Crespo, Sheila Jandhyra Vianna; Mendes, Luis Fernando [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil); Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia

    2001-06-01

    Closed loop obstruction of the bowel is an extremely grave condition that may lead to serious consequences and even be fatal. The authors describe a case of a patient with intestinal obstruction secondary to cancer of the sigmoid and highlight the importance of computed tomography in the analysis of the pathological changes in routine management of patients with acute abdomen. (author)

  13. Study of noise sources of image for optimization of radiation doses in skull computerized tomography; Estudo das fontes de ruido da imagem para fins de otimizacao das doses na tomografia computadorizada de cranio

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, R.B.; Garos, K.A.C. [UNIFESP - Universidade Federal de Sao Paulo, SP (Brazil)]. E-mail: rbitelli@cfrh.epm.br

    2001-07-01

    Our goal was to evaluate the exposure factors that can change the image noise of head CT in different slices thicknesses. We have evaluated the images noise at several mAs varying from 50 to 800 mAs for 100, 120 and 140 kVp as tension values. The images uniformity were determined for all technical exposure conditions. We did not observed any important noise reduction for values up 200 mAs which can justify the increase of radiation doses through the increase of mAs. (author)

  14. Halo sign nodules in angio invasive pulmonary aspergillosis: correlation of high-resolution computed tomography findings with anatomopathology; Nodulos com sinal do halo na aspergilose pulmonar angioinvasiva: correlacao da tomografia computadorizada de alta resolucao com a anatomopatologia

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia; Valiante, Paulo Marcos [Universidade Federal, Rio de Janeiro, RJ (Brazil). Dept. de Patologia; Souza Junior, Arthur Soares [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Disciplina de Radiologia

    2002-08-01

    The aim of this study was to correlate the early findings observed on high-resolution computed tomography with anatomopathology results of patients with angio invasive aspergillosis. The authors studied two patients with leukemia. The nodules seen on high-resolution computed tomography corresponded to areas of hemorrhagic infarction, necrotic coagulation and fungal hyphae infiltration whereas ground glass halo corresponded to intra alveolar hemorrhage. Nodules with halo sign were closely correlated with anatomopathology findings. We concluded that the anatomopathology findings can clearly explain the image features of the lesions observed on high-resolution computed tomography. (author)

  15. Implantation of tomography qualities in Centro Regional de Ciencias Nucleares do Nordeste, Brazil; Implantacao das qualidades de tomografia no Centro Regional de Ciencias Nucleares do Nordeste, CNEN-PE, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Diniz, Osana F.; Silveira, Renata R.; Melo, Roberto T.; Oliveira, Marcia L., E-mail: osana.diniz@hotmail.com [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PB (Brazil)

    2016-07-01

    The quality guarantee of the service offered by a ionizing radiation metrology laboratory is deeply connected to the conformity to the radiation beams implanted to the determination and definition present in the international standards and adopted by the Brazilian National Commission of Nuclear Energy – CNEN. The objective of this work was the implementation of computerized tomography qualities, RQT 8, 9 e 10, in accordance with the IEC-61267 standard in the Metrology Laboratory of the Northeast Regional Center of Nuclear Sciences (CRCN-NE), PE, Brazil. (author)

  16. Does negative retroperitoneal CT in adolescents with paratesticular rhabdomyosarcoma preclude the need of retroperitoneal lymph node dissection?; A tomografia de retroperitoneo normal em adolescentes com rabdomiossarcoma paratesticular afasta necessidade de linfadenectomia?

    Energy Technology Data Exchange (ETDEWEB)

    Damazio, Eulalio [Hospital Lucano, Teresina (PI) (Brazil); Caran, Eliana [Instituto de Oncologia Pediatrica, Universidade Federal de Sao Paulo - UNIFESP, Sao Paulo, SP (Brazil); Ortiz, Valdemar; Macedo Junior, Antonio, E-mail: macedo.dcir@epm.br [Departamento de Urologia, Universidade Federal de Sao Paulo - UNIFESP, Sao Paulo, SP (Brazil)

    2011-07-01

    We report on a 16-year-old male with paratesticular rhabdomyosarcoma who underwent retroperitoneal lymph node dissection due to a stage I tumor (normal retroperitoneal computed tomography). The surgical finding was three enlarged nodes, positive for metastatic disease. Patient was referred to adjuvant chemotherapy. This case suggests that the Intergroup Rhabdomyosarcoma Study Group IV protocol is subject to questions regarding adolescents with paratesticular rhabdomyosarcoma, and that negative retroperitoneal CT does not preclude the need of lymph node dissection. (author)

  17. Ground-glass opacity in diffuse lung diseases: high-resolution computed tomography-pathology correlation; Opacidades em vidro fosco nas doencas pulmonares difusas: correlacao da tomografia computadorizada de alta resolucao com a anatomopatologia

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Maria Lucia de Oliveira; Vianna, Alberto Domingues; Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia; Souza Junior, Arthur Soares [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Disciplina de Radiologia; Moraes, Heleno Pinto de [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Patologia]. E-mail: edmarchiori@zipmail.com.br

    2003-12-01

    Ground-glass opacity is a finding frequently seen in high-resolution computed tomography examinations of the chest and is characterized by hazy increased attenuation of lung, however without blurring of bronchial and vascular margins. Due to its un specificity, association with other radiological, clinical and pathological findings must be considered for an accurate diagnostic interpretation. In this paper were reviewed 62 computed tomography examinations of patients with diffuse pulmonary diseases of 14 different etiologies in which ground-glass opacity was the only or the most remarkable finding, and correlated this findings with pathology abnormalities seen on specimens obtained from biopsies or necropsies. In pneumocystosis, ground-glass opacities correlated histologically with alveolar occupation by a foaming material containing parasites, in bronchiole alveolar cell carcinoma with thickening of the alveolar septa and occupation of the lumen by mucus and tumoral cells, in paracoccidioidomycosis with thickening of the alveolar septa, areas of fibrosis and alveolar bronchopneumonia exudate, in sarcoidosis with fibrosis or clustering of granulomas and in idiopathic pulmonary fibrosis with alveolar septa thickening due to fibrosis. Alveolar occupation by blood was found in cases of leptospirosis, idiopathic hemo siderosis, metastatic kidney tumor and invasive aspergillosis whereas oily vacuole were seen in lipoid pneumonia, proteinaceous and lipo proteinaceous material in silico proteinosis and pulmonary alveolar proteinosis, and edematous fluid in cardiac failure. (author)

  18. Experimental measurement of the scatter fraction in skull and body CT for teams 64- slice computed tomography; Medida experimental de la fraccion de dispersion TC en craneo y cuerpo para equipo de tomografia computarizada de 64 cortes

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, G.; Haro, G.; Herrador, M.

    2011-07-01

    Different formalisms for the calculation of shielding in Cf equipment, the proposed document 147 of NCRP are widely accepted. Of the three methods mentioned in the protocol, two involve the use of two independent factor a of equipment, called scatter fraction CT in skull and body. Interestingly, the experimental measurement of the same, especially in those models following the publication of the document, which are also coincides with the highest number of detector channels and overall a greater radiation beam in the z axis.

  19. On-line course as tools for radiation protection training in patients. A practical case in computerized tomography; El Aula Virtual como herramienta para la formacion en PR del paciente; caso practico en tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Medina Campos, J.; Fernandez Tallon, J.; Busca Suau, J.; Baro Casanovas, J.

    2006-07-01

    The rise in ionizing radiation applications within the field of diagnostics, with the corresponding increase in both number and doses received by patients, requires adequate resources for education and training in radiological protection. In is quite difficult to assemble professionals at a specific place to carry out training. However, the use of Information and Communication Technologies (IT) makes it possible to carry out training. However, the use of Information and Communication Technologies (IT) makes it possible to carry out training through Internet in an effective, easy and amusing way (e-learning). An on-line course of patient radiological protection and quality control in computer tomography has been developed aimed at professionals that use these diagnostic techniques. The course has been run twice in the period 2005-2006. The course is found on an Internet-accessible Virtual Campus, which allows access to multimedia contents, communication between students and instructors and follow-up of students performance. Final evaluation is done on-line and successfully passing the course counts for 8.9 credits in the Continuous Education Programme of Spanish Health Systems. (Author)

  20. Development of a pediatric chest phantom for dosimetry in computerized tomography; Desenvolvimento de objeto simulador de tórax pediátrico para dosimetria em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Aburjaile, W.N.; Mourão, A.P., E-mail: wadia.namen@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Oliveira, F.A. [Centro Federal de Educação Tecnológica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Centro de Engenharia Biomédica

    2017-07-01

    Computed Tomography (CT) has promoted a significant increase in the dose absorbed by patients due to the diagnosis. Therefore, it is indispensable to improve protocols, using smaller doses, without impairing the diagnostic quality of the image. The risks of stochastic effects are greater for children due to tissue radiosensitivity coupled with longer life expectancy. In the work, a cylindrical simulator was used, representing an adult thorax, made of polymethylmethacrylate, and a second simulator object of the same material was developed in oblong format including the axillary regions based on the dimensions of the pediatric patient's 8-year-old chest. A comparative study was performed between chest scans performed on two CT equipment in different radiodiagnostic services. The central slice of the two simulating objects was irradiated successively and, using a pencil-type ionization chamber, the absorbed dose was measured at five different points of each simulating object. From the measurements, weighted Dose and Volumetric Dose Index (CK, PMMA, vol) values were obtained for the 10 cm sweep of the central region of the object, in helical mode. The scans were performed using the chest acquisition protocols used by radiodiagnostic services, both for a supply voltage of the 120 kV X-ray tube. The study allowed to compare the variation of absorbed dose between patients with distinct chest volumes and the patient dose variation between two devices when used for the generation of images with the same diagnostic objective.

  1. Proposal of recommendations for quality control in computerized tomography, with emphasis in new technologies; Proposta de um protocolo de controle de qualidade em tomografia computadorizada, com enfase nas novas tecnologias

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Marlon da Silva Brandao; Neves, Camila Nascimento das

    2016-11-01

    The use of computed tomography (CT) has continuously grown over the years and expanding its applications in different medical procedures. As a result, there was an increase of frequency and in collective dose. One of the strategies to maximize the benefits of this important imaging modality is the implementation of optimization of protection programs. As part of this process, a quality control should be established to ensure the correct performance of the scanner. Quality control protocols can be very useful to carry out all tests in a standard methodology and well-established tolerance values. However, to keep up with the constant advances in technology, these protocols must be constantly reviewed and updated to allow its application in different existing models. The objective of this work is to develop a quality control protocol based on international recommendations and in national standards. (author)

  2. Dipyridamole stress myocardial perfusion by computed tomography in patients with left bundle branch block; Perfusao miocardica de estresse com dipiridamol por tomografia computadorizada em pacientes com bloqueio de ramo esquerdo

    Energy Technology Data Exchange (ETDEWEB)

    Cabeda, Estevan Vieira; Rochitte, Carlos Eduardo; Nomura, Cesar Higa; Parga, Jose Rodrigues; Avila, Luiz Francisco Rodrigues; Falcao, Andrea Maria Gomes; Soares Junior, Jose [Instituto do Coracao (InCor), Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil)

    2015-12-15

    Background: Functional tests have limited accuracy for identifying myocardial ischemia in patients with left bundle branch block (LBBB). Objective: To assess the diagnostic accuracy of dipyridamole-stress myocardial computed tomography perfusion (CTP) by 320-detector CT in patients with LBBB using invasive quantitative coronary angiography (QCA) (stenosis ≥ 70%) as reference; to investigate the advantage of adding CTP to coronary computed tomography angiography (CTA) and compare the results with those of single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy. Methods: Thirty patients with LBBB who had undergone SPECT for the investigation of coronary artery disease were referred for stress tomography. Independent examiners performed per-patient and per-coronary territory assessments. All patients gave written informed consent to participate in the study that was approved by the institution's ethics committee. Results: The patients' mean age was 62 ± 10 years. The mean dose of radiation for the tomography protocol was 9.3 ± 4.6 mSv. With regard to CTP, the per-patient values for sensitivity, specificity, positive and negative predictive values, and accuracy were 86%, 81%, 80%, 87%, and 83%, respectively (p = 0.001). The per-territory values were 63%, 86%, 65%, 84%, and 79%, respectively (p < 0.001). In both analyses, the addition of CTP to CTA achieved higher diagnostic accuracy for detecting myocardial ischemia than SPECT (p < 0.001). Conclusion: The use of the stress tomography protocol is feasible and has good diagnostic accuracy for assessing myocardial ischemia in patients with LBBB. (author)

  3. Gamma camera based Positron Emission Tomography: a study of the viability on quantification; Tomografia por emissao de positrons com sistemas PET/SPECT: um estudo da viabilidade de quantifizacao

    Energy Technology Data Exchange (ETDEWEB)

    Pozzo, Lorena

    2005-07-01

    Positron Emission Tomography (PET) is a Nuclear Medicine imaging modality for diagnostic purposes. Pharmaceuticals labeled with positron emitters are used and images which represent the in vivo biochemical process within tissues can be obtained. The positron/electron annihilation photons are detected in coincidence and this information is used for object reconstruction. Presently, there are two types of systems available for this imaging modality: the dedicated systems and those based on gamma camera technology. In this work, we utilized PET/SPECT systems, which also allows for the traditional Nuclear Medicine studies based on single photon emitters. There are inherent difficulties which affect quantification of activity and other indices. They are related to the Poisson nature of radioactivity, to radiation interactions with patient body and detector, noise due to statistical nature of these interactions and to all the detection processes, as well as the patient acquisition protocols. Corrections are described in the literature and not all of them are implemented by the manufacturers: scatter, attenuation, random, decay, dead time, spatial resolution, and others related to the properties of each equipment. The goal of this work was to assess these methods adopted by two manufacturers, as well as the influence of some technical characteristics of PET/SPECT systems on the estimation of SUV. Data from a set of phantoms were collected in 3D mode by one camera and 2D, by the other. We concluded that quantification is viable in PET/SPECT systems, including the estimation of SUVs. This is only possible if, apart from the above mentioned corrections, the camera is well tuned and coefficients for sensitivity normalization and partial volume corrections are applied. We also verified that the shapes of the sources used for obtaining these factors play a role on the final results and should be delt with carefully in clinical quantification. Finally, the choice of the region of interest is critical and it should be the same used to calculate the correction factors. (author)

  4. Preparation of an application for the control of the dose delivered by equipment of computed tomography (CT); Elaboracion de una aplicacion para el control de la dosis impartida por equipos de tomografia computerizada (TC)

    Energy Technology Data Exchange (ETDEWEB)

    Torres Cabrera, R.; Agulla Otero, M.; Hernando Gonzalez, I.

    2013-07-01

    Although TC are native digital equipment, the collection and treatment of the doses given to the patients it continues to present difficulties to date, especially in the still very large number of teams that do not produce a formal report of dose (SR). This work shows the experience gained in the development of an application that allows the calculation, monitoring and control of the dose given to patients by teams of TC. (Author)

  5. Descrição anatômica das estruturas osteoarticulares do esqueleto axial do tatu-galinha (Dasypus novemcinctus Linnaeus, 1758) por meio da radiografia e tomografia computadorizada

    OpenAIRE

    Alves, Lidiane da Silva [UNESP

    2016-01-01

    O tatu-galinha é um dos animais mais populosos da ordem Xenarthra com distribuição do sul dos Estados Unidos até a América do Sul. São animais frequentemente caçados e, em muitos casos, são vítimas de atropelamentos rodoviários. Existem diversos estudos descritivos sobre a fisiologia, a genética e o comportamento, porém a anatomia óssea e articular destes animais ainda é restrita. Este estudo tem por objetivo, descrever a anatomia das estruturas osteoarticulares do esqueleto axial em 20 tatus...

  6. Dosimetric evaluation of cone beam computed tomography scanning protocols; Avaliação dosimétrica de protocolos de exame de tomografia computadorizada de feixe cônico

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Maria Rosangela

    2015-07-01

    It was evaluated the cone beam computed tomography, CBCT scanning protocols, that was introduced in dental radiology at the end of the 1990's, and quickly became a fundamental examination for various procedures. Its main characteristic, the difference of medical CT is the beam shape. This study aimed to calculate the absorbed dose in eight tissues / organs of the head and neck, and to estimate the effective dose in 13 protocols and two techniques (stitched FOV e single FOV) of 5 equipment of different manufacturers of cone beam CT. For that purpose, a female anthropomorphic phantom was used, representing a default woman, in which were inserted thermoluminescent dosimeters at several points, representing organs / tissues with weighting values presented in the standard ICRP 103. The results were evaluated by comparing the dose according to the purpose of the tomographic image. Among the results, there is a difference up to 325% in the effective dose in relation to protocols with the same image goal. In relation to the image acquisition technique, the stitched FOV technique resulted in an effective dose of 5.3 times greater than the single FOV technique for protocols with the same image goal. In the individual contribution, the salivary glands are responsible for 31% of the effective dose in CT exams. The remaining tissues have also a significant contribution, 36%. The results drew attention to the need of estimating the effective dose in different equipment and protocols of the market, besides the knowledge of the radiation parameters and equipment manufacturing engineering to obtain the image. (author)

  7. CF findings of bowel infarction in 56 surgical patients, 5 of whom with reversible ischemia; Aspetti alla tomografia computerizzata dell'infarto intestinale. 56 pazienti sottoposti a interventi chirurgico di cui 5 con ischemia mesenterica reversibile.

    Energy Technology Data Exchange (ETDEWEB)

    Salzano, A.; De Rosa, A.; Carbone, M.; Ginolfi, F.; Rossi, E.; Amodio, F. [Naples Univ. Federico 2. (Italy). Ist. di Scienze Radiologiche; Muto, M.; Tuccillo, M. [Azienda Sanitaria di Rilievo Nazionale A. Cardarelli, Naples (Italy). Servizio di Neuroradiologia

    1999-04-01

    Bowel infarction is a rare and typical condition of the elderly; despite improvements in diagnostic imaging and vascular surgery, bowel infarction remains a major cause of acute abdomen, with mortality rates ranging 70-80%. Diagnosis on often late because clinical signs, laboratory data and radiologic findings are a specific. The authors investigated radiographic and particular CT patterns of intestinal infraction in 56 patients submitted to surgery within 12 hours of admission. We also report the CT findings of 5 of these patients who had reversible mesenteric ischemia. CT is more sensitive than radiography and does not exhibit the limitations of angiography (i.e., invasiveness, radiation exposure and complex organization). Therefore CT can presently be considered the method of choice in patients with suspected bowel infarction. [Italian] L'infarto intestinale rappresenta una malattia rara e tipica del soggeto anziano; nonostante il notevole perfezionamento delle tecniche di diagnostica per immagini e il progresso della chirurgia vascolare, rimane ancora oggi una delle piu' temibili condizioni di addome acuto, con mortalita' superiore al 70-80%. Il riconoscimento diagnostico e' tardivo per l'aspecificita' dei dati di laboratorio, dei segni clinici e degli esami radiologici. La TC presenta maggiore afficacia diagnostica rispetto all'esame radiografico diretto e non ha limiti che caratterizzano l'angiografia, quali l'invasivita', radioesposizione e complessita' organizzativa: attualmente la metodica TC puo' essere indicata come indagine di scelta in pazienti con sospetto infarto intestinale.

  8. Bioelectrical impedance and visceral fat: a comparison with computed tomography in adults and elderly; Bioimpedancia eletrica e gordura visceral: uma comparacao com a tomografia computadorizada em adultos e idosos

    Energy Technology Data Exchange (ETDEWEB)

    Eickemberg, Michaela [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil); Roriz, Anna Karla Carneiro [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil); Fontes, Gardenia Abreu Vieira [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil); Sampaio, Lilian Ramos [Universidade Federal de Sao Paulo (Unifesp), Sao Paulo, SP (Brazil)

    2013-05-01

    Objective: To evaluate the association between electrical bioimpedance analysis (BIA) and visceral fat (VF) in adult and elderly patients. Subjects and methods: This was a cross-sectional study, with a sample of 191 subjects (52% women, 49% elderly) stratified by sex, age and body mass. Computerized tomography (VF area) and BIA (percentage of total body fat (%TBF-BIA), phase angle, reactance and resistance) data were generated. Statistical analysis was based on Pearson's Correlation Coefficient, Anova, Pearson's Chi-square, and ROC curves. Results: VF areas {>=} 130 cm{sup 2} were more prevalent among the elderly and among men. Adult females showed a stronger correlation between GV and %TBF-BIA. The other groups showed similar results and statistically significant correlations. Correlations between GV and phase angle were weak and not statistically significant. ROC Curves analyzes showed the following %TBF-BIA, which identified excess VF: for male subjects: 21.5% (adults) and 24.25% (elderly); for female subjects: 35.05% (adults) and 38.45% (elderly) with sensitivity of 78.6%, 82.1%, 83.3%, and 66.7%, and specificity of 70.6%, 62.5%, 79.1%, and 69%, respectively. Conclusion: BIA was found to have satisfactory sensitivity and specificity to predict VF; however, other devices and other techniques should be investigated to improve VF prediction. (author)

  9. Preliminary evaluation of exposures of computerized tomography patients in Latin America: IAEA project RLA/9/67; Avaliacao preliminar das exposicoes de pacientes em tomografia computadorizada na America Latina: Projeto IAEA RLA/9/67

    Energy Technology Data Exchange (ETDEWEB)

    Kodlulovich, S.; Silveira, V. [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil); Khoury, H.J. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamcnto de Energia Nuclear; and others

    2013-07-01

    The aim of this study was to obtain preliminary values of reference levels in CT . Were sent to each country forms with information of radiological protection and routine CT protocols. The CT dose index and absorbed dose to organs was estimated from the technical data for each equipment . The results showed that the total number of examinations performed 92 % are adult patients and 8 % are children. The most frequent examination of the skull was adult (40 % ) and abdomen for children (42 % ) . About the service , 67 % of the equipment are multicut and 76 % have specific protocols for pediatric patients. The CTDI{sub vol} values for head exams of adults vary between 2 and 352 mGy for pediatric patients under 1 year 1-191 mGy under 7 years old 5-335 mGy. For chest values ranged from 3 to 26 mGy for adults, between 1 and 89 mGy for children under 1 year and between 3-114 mGy for children between 1 and 7 years. Exams of the abdomen/pelvis of adults the range was 3-47 mGy , between 4-90 mGy for children under 1 year and between 2-31 mGy for children between 1 and 7 years. This study showed that although there are pediatric protocols, there is a wide variation in values of CTDl{sub vol} indicating a high potential for dose reduction. This result requires immediate action for optimization and implementation of diagnostic reference values in Latin America.

  10. Use of Monte Carlo simulation software for the calculation of the effective dose in cone beam Tomography; Uso del software de simulacion Monte Carlo para el calculo de la dosis efectiva en Tomografia de haz conico

    Energy Technology Data Exchange (ETDEWEB)

    Gomes B, W. O., E-mail: wilsonottobatista@gmail.com [Instituto Federal da Bahia, Rua Emidio dos Santos s/n, Bardalho, 40301-015 Salvador, Bahia (Brazil)

    2015-10-15

    Full text: In this study irradiation geometry applicable to PCXMC and the consequent calculation of effective dose in applications of cone beam computed tomography (CBCT) was developed. Two different CBCT equipment s for dental applications were evaluated: Care Stream Cs-9000 3-Dimensional and Gendex GXCB-500 tomographs. Each protocol initially was characterized by measuring the surface kerma input and the product air kerma-area, P{sub KA}. Then, technical parameters of each of the predetermined protocols and geometric conditions in the PCXMC software were introduced to obtain the values of effective dose. The calculated effective dose is within the range of 9.0 to 15.7 μSv for Cs 9000 3-D and in the range 44.5 to 89 mSv for GXCB-500 equipment. These values were compared with dosimetric results obtained using thermoluminescent dosimeters implanted in anthropomorphic mannequin and were considered consistent. The effective dose results are very sensitive to the radiation geometry (beam position); this represents a factor of fragility software usage, but on the other hand, turns out to be a very useful tool for quick conclusions regarding the optimization process of protocols. We can conclude that the use of Monte Carlo simulation software PCXMC is useful in the evaluation of test protocols of CBCT in dental applications. (Author)

  11. Bioelectrical impedance and visceral fat: a comparison with computed tomography in adults and elderly; Bioimpedancia eletrica e gordura visceral: uma comparacao com a tomografia computadorizada em adultos e idosos

    Energy Technology Data Exchange (ETDEWEB)

    Eickemberg, Michaela [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil); Roriz, Anna Karla Carneiro [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil); Fontes, Gardenia Abreu Vieira [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil); Sampaio, Lilian Ramos [Universidade Federal de Sao Paulo (Unifesp), Sao Paulo, SP (Brazil)

    2013-05-01

    Objective: To evaluate the association between electrical bioimpedance analysis (BIA) and visceral fat (VF) in adult and elderly patients. Subjects and methods: This was a cross-sectional study, with a sample of 191 subjects (52% women, 49% elderly) stratified by sex, age and body mass. Computerized tomography (VF area) and BIA (percentage of total body fat (%TBF-BIA), phase angle, reactance and resistance) data were generated. Statistical analysis was based on Pearson's Correlation Coefficient, Anova, Pearson's Chi-square, and ROC curves. Results: VF areas {>=} 130 cm{sup 2} were more prevalent among the elderly and among men. Adult females showed a stronger correlation between GV and %TBF-BIA. The other groups showed similar results and statistically significant correlations. Correlations between GV and phase angle were weak and not statistically significant. ROC Curves analyzes showed the following %TBF-BIA, which identified excess VF: for male subjects: 21.5% (adults) and 24.25% (elderly); for female subjects: 35.05% (adults) and 38.45% (elderly) with sensitivity of 78.6%, 82.1%, 83.3%, and 66.7%, and specificity of 70.6%, 62.5%, 79.1%, and 69%, respectively. Conclusion: BIA was found to have satisfactory sensitivity and specificity to predict VF; however, other devices and other techniques should be investigated to improve VF prediction. (author)

  12. Comparative analysis of quality control tests on computed tomography in accordance with national and international laws; Analise comparativa dos testes de controle de qualidade em tomografia computadorizada de acordo com as legislacoes nacional e internacional

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Fernando S.; Vasconcelos, Rebeca S.; Goncalves, Marcel S.; Oliveira, Marcus V.L. de, E-mail: fernando_siramos@hotmail.com, E-mail: marcusradiology@gmail.com [Instituto Federal da Bahia (IFBA), Salvador, BA (Brazil)

    2014-07-01

    The objective of this study is to perform a comparative analysis between the Brazilian legislation and internationals protocols, with respect to the quality control tests for computerized tomography. We used 07 references, published from 1998-2012: the Protocolo Brasileiro - Portaria 453/98 SVS/MS and the Guia de Radiodiagnostico Medico da ANVISA; Quality Assurance Programme for Computed Tomography: Diagnostic and Therapy Applications of the IAEA; European Protocol - European Guidelines on Quality Criteria for Computed Tomography of the EUR No. 16262 EN; Radiation Protection No. 162 - Criteria for Acceptability of Medical Radiology, Nuclear Medicine and Radiotherapy of the European Commission; the Protocols of Control de Calidad en Radiodiagnostico IAEA / ARCAL XLIX; and the Protocolo Espanol de Control de Calidad en Radiodignostico. The comparative analysis of these legislations was based on aspects of tolerance / limit, frequency and objectives of the recommended tests. Were found 18 tests in the Brazilian legislation. The tests were grouped according to their nature (dosimetric tests / exposure and geometric tests and image quality tests). Among the evaluated protocols was identified divergence between tests contained in the documents and the criteria of assessment set out in this work. It is clear, moreover, that for certain documents are not observed tolerances, well-defined methodologies and even frequency of testing. We conclude that the current legislation in Brazil differs in certain respects from international protocols analyzed, although this has a great numbers of quality control tests. However, it is necessary that the Brazilian legislation takes into account technological advances presented to time.

  13. Diagnosis of chronic rhino sinusitis in patients with cystic fibrosis: correlation between anamnesis, nasal endoscopy and computed tomography; Diagnostico de rinossinusite cronica em pacientes com fibrose cistica: correlacao entre anamnese, nasofibroscopia e tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Boari, Leticia; Castro Junior, Ney Penteado de [Faculdade de Ciencias Medicas da Santa Casa de Sao Paulo, SP (Brazil)]. E-mail: curyboari@uol.com.br

    2005-11-15

    The sinonasal involvement is one of the most common manifestations in cystic fibrosis. Data show a high incidence of chronic rhino sinusitis in these patients. Although it has been found radiographic opacification of the sinus in more than 90% of cases, few are symptomatic. So that, it is difficult to recognize nasossinusal disease in patients with cystic fibrosis. Questionnaire, nasal endoscopy and CT-scan are very important methods in this approach. Aim: to evaluate the diagnosis of chronic rhino sinusitis in patients with cystic fibrosis by anamnesis, nasal endoscopy and CT-scan and compare those results.Study Design: Clinical prospective. Material and method: evaluation of 34 patients - older than 6 years and with a confirmed diagnoses of cystic fibrosis - by anamnesis (questionnaire), nasal endoscopy (score Lund-Kennedy) and CT-scan (score Lund-Mackay). Results: chronic rhino sinusitis was confirmed in: 20,58% of cases by the questionnaire, 73,52% of the cases by the nasal endoscopy and in 93,54% of the cases by the CT-scan. The results showed significant differences. The correlation between nasal endoscopy score (Lund-Kennedy score) and CT-scan score (Lund-Mackay score) was statistically significant. Conclusion: the diagnosis of chronic rhino sinusitis was statistically different between the three methods. It was higher in imaging analysis and lower in questionnaire. The nasal endoscopy is an excellent method to evaluate nasossinusal disease in cystic fibrosis. (author)

  14. Evaluation of X ray radiation doses in pediatric examinations of cranial computerized tomography based on optimization studies; Avaliacao das doses de radiacao X em exames pediatricos de tomografia computadorizada de cranio com base em estudos de otimizacao

    Energy Technology Data Exchange (ETDEWEB)

    Daros, Kellen Adriana Curci

    2005-07-01

    This paper identifies the technical conditions for CT examination which offers lowest absorbed dose and to attend the manufacturer recommendations as far the spatial resolution is concerned. The paper evaluates the absorbed dose during cranial CT in up to 6 years children satisfying the technical condition recommended by the manufacturer and routine clinical conditions. The paper also established a quantitative relationship among the absorbed dose and its distribution in the cranial regions of pediatric patients up to 6 years old in a way to estimate the doses subject to optimized conditions

  15. Image quality and volume computed tomography air kerma index (C{sub vol}) evaluation in Recife; Avaliacao da qualidade de imagem e do indice volumetrico de Kerma ar em tomografia computadorizada (C{sub vol}) em Recife

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Marcos Ely Almeida

    2008-07-01

    The Computed Tomography (CT) is an important diagnostic imaging method, widely used. However, in spite of all the advantages and technologic advances within the CT scanners, the tomographic procedures result in high absorbed doses to patients. The main objective of this work was to perform a dosimetric study of CT scanners located at Recife and to evaluate the image quality on CT examinations in these equipment. The volume CT air kerma index (C{sub VOL}) and air kerma length product (P{sub KL,CT}) were estimated. These values were calculated using normalized weighted air kerma indexes in CT standard dosimetry phantoms ({sub n}C{sub W}), supplied by ImPACT group for several CT scanners, and the scan parameters of routine head, routine chest and hi-resolution chest CT exams performed at 20 institutions. The irradiation parameters of 15 adult patients for each CT procedure were registered at six participating centres, at which the phantom from the American College of Radiology (ACR) CT accreditation protocol was used for the image quality measurements. For routine head exams, the C{sub VOL} values varied between 12 and 58 mGy (at the posterior fossa) and 15 to 58 mGy (at the cerebrum) and the P{sub KL,CT}, from 150 to 750 mGy{center_dot}cm. The C{sub VOL} values for routine chest procedures varied from 3 to 26 mGy and the P{sub KL,CT}, between 120 and 460 mGy{center_dot}cm. In relation to Hi-resolution chest exams, C{sub VOL} values were from 1.0 to 2.7 mGy and the P{sub KL,CT} values varied between 24 and 67 mGy{center_dot}cm. The image quality evaluations results showed that almost all scanners presented at least one inadequacy. One of the equipment presented faults at 70% of the tests. With regard to the image noise, only two scanners presented acceptable results. From these results, it is possible to conclude that the volume CT air kerma index values are lower than the European reference levels. However, the image quality of these CT scanners does not attend the ACR requirements, suggesting the need to implement quality assurance programs at the evaluated institutions. (author)

  16. Muscle areas of lower limbs were determined by anthropometric and computed tomography in the adult of the masculine sex; Areas musculares del muslo y la pierna estimadas por antropometria y tomografia axial computadorizada en varones adultos

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Vieitez, Jorge Alberto; Alvarez Cuesta, Jose Alberto; Williams Wilson, Luis [Centro Provincial de Medicina del Deporte, Holguin (Cuba)

    2000-07-01

    In a sample of 17 males (age 26 {sup +}{sub -} 5 years; weight 76.3 {sup +}{sub -} 7.1 kg and height 177.2 {sup +}{sub -} 3.9 cm) the differences, ratios and interchangeability among muscle areas (cm{sup 2}) of lower limbs (medial thigh and maximum leg) were determined by anthropometric (muscle area= [limb circumference (cm)- 0.31416 skinfold (mm)]2 /12.5664 and computed tomography. The anthropometric method overestimated muscle areas in both regions (thigh + 9.0 {sup +}{sub -} 12.8; p= 0.01 and leg: +8.5 {sup +}{sub -} 11.2; p=0.006). Relation between the two procedures was statistically significant (thigh r=0.9; p= 8.8 .10-7 and leg r=0.52; p=0.03). Both methods were interchangeable since neither the correlation coefficient (thigh r=0.42; leg r=0.38) nor the regression gradient (thigh b {sub {sub 0.21}} {sup +}{sub -} 0.12; leg b = -0.44{sup +}{sub -} 0.28) between the differences (anthropometric ? TAC) and the averages (anthropometric + TAC/ 2) in both methods were statistically significant (p>0.05). It was concluded that the anthropometric method requires certain adjustments to be able to estimate more accurately the muscle areas of lower limbs.

  17. Diagnostic value of positron emission tomography/computed tomography with fluorine-18 fluorodeoxyglucose in patients with differentiated thyroid gland carcinoma, high thyroglobulin serum levels and negative iodine whole body scan; Valor diagnostico da tomografia por emissao de positrons/tomografia computadorizada (PET-CT) com fluor-18 fluordeoxiglicose (FDG-{sup 18}F) em pacientes com carcinoma diferenciado da tireoide, niveis sericos de tireoglobulina elevados e pesquisa de corpo inteiro com iodo negativa

    Energy Technology Data Exchange (ETDEWEB)

    Yamaga, Lilian Yuri Itaya; Cunha, Marcelo Livorsi da; Wagner, Jairo; Thom, Annelise Fischer; Daniel, Mauro Miguel; Funari, Marcelo B. de Gusmao [Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil). Dept. de Imagem]. E-mail: itaya@einstein.br

    2007-06-15

    Purpose: To evaluate the role of PET-CT with FDG-{sup 18}F in the detection of recurrence and/or metastasis of differentiated thyroid carcinoma (DTC) in patients with elevated levels of thyroglobulin (TG) and negative whole body scan (WBS). Patients and method: PET-CT findings of 25 patients were compared to histopathology evaluation and conventional imaging (CI). Results: PET-CT scan was positive in 16 patients finding 14 true-positive and 2 false-positive cases (positive predictive value 87.5%). Nine patients had negative PET-CT; two had decrease of TG to undetectable levels. One patient had residual disease detected by post-therapeutic WBS. Six patients had no evidence of tumor during follow-up (mean time 16 months). PET-CT was concordant with CI in 52%, partially concordant in 12% and discordant in 36% (6 false-negatives and 3 false-positive of CI). We observed a tendency of increasing proportion of positive PET-CT with increasing TG. Conclusion: PET-CT scan with FDG-{sup 18}F is useful in the detection of recurrence and/or metastases of DTC with high TG levels but negative WBS. It presents elevated positive predictive value and is superior to CI being more effective as higher the serum TG levels. (author)

  18. Biodegradation of Crude-oil by Fungi Isolated from Cow ...

    African Journals Online (AJOL)

    ... fungi identified from the contaminated soils include; Bdellospora helicoides, Aspergillus fumigatus, Gonadobotricum apiculata, Aspergillus niger, Trichoderma viridae, Pleurothecium recurvatum, Streptothrix atra, Thysarophora longispora, Candida albicans, Aspergillus flavus, Helminthosporium velutinum, Botrytis cinerea, ...

  19. Magnon contribution to electrical resistance of gadolinium-dysprosium alloy single crystals

    International Nuclear Information System (INIS)

    Nikitin, S.A.; Slobodchikov, S.S.; Solomkin, I.K.

    1978-01-01

    The magnon, phonon and interelectron collision contributions to the electric resistance of single crystals of gadolinium-dysprosium alloys were quantified. A relationship was found to exist between the electric resistance and the variation of the topology of the Fermi surface on melting of gadolinium with dysprosium. It was found that gadolinium-dysprosium alloys, which have no helicoidal magnetic structure in magnetically ordered state, feature a spin-spin helicoidal-type correlations in the paramagnetic field

  20. Variáveis capnográficas pré e pós-tromboendarterectomias pulmonares Pre and post-pulmonary thromboendarterectomies campnographic variables

    Directory of Open Access Journals (Sweden)

    Marcos Mello Moreira

    2007-12-01

    Full Text Available Este relato de dois casos com os resultados da fração tardia de espaço morto (fDlate, fração do espaço morto alveolar end-tidal (AVDSf, gradiente artério-alveolar de CO2 [P(a-etCO2] e slope da fase 3 do espirograma, submetidos à tromboendarterectomia pulmonar por tromboembolismo pulmonar (TEP. O TEP foi diagnosticado pela cintilografia pulmonar, tomografia helicoidal computadorizada e por arteriografia pulmonar. O cálculo da fDlate, AVDSf e P(a-etCO2 baseou-se na capnografia volumétrica associada à gasometria arterial. A fDlate préoperatória do primeiro paciente foi de 0,16 (cutoff de 0,12 e a AVDSf = 0,30 (cutoff de 0,15. Já a fDlate do segundo paciente resultou falso-negativa (0,01, embora a AVDSf resultasse positiva (0,28. A fDlate pós-operatória do primeiro paciente foi de -0,04 e a AVDSf de 0,16; a fDlate do segundo paciente foi de 0,07 e a AVDSf = 0,28. A associação destas variáveis com os exames por imagem reforça a importância deste método como ferramenta diagnóstica não-invasiva no diagnóstico de TEP.In these case report, the results of late dead space fraction (fDlate, end-tidal alveolar dead space fraction (AVDSf, arterial-alveolar gradient CO2 [P(a-etCO2], and slope phase 3 of spirogram of two patients who underwent thromboendarterectomy for pulmonary embolism (PE are shown. PE was diagnosed by pulmonary scintigraphy, helical tomography, and pulmonary angiography. The calculation of fDlate, AVDSf and P(a-etCO2 was based on volumetric capnography associated with arterial blood gas analysis. The pre-operative fDlate of the first patient was 0.16 (cutoff 0.12 and AVDSf was 0.30 (cutoff 0.15. However, the fDlate of the second patient was false-negative (0.01 but, the AVDSf was positive (0.28. Postoperative fDlate of the first patient was -0.04 and AVDSf was 0.16; for the second patient, the values were 0.07 and 0.28, respectively. The association of these capnographic variables with image exams reinforces the

  1. New geometries for black hole horizons

    Energy Technology Data Exchange (ETDEWEB)

    Armas, Jay [Physique Théorique et Mathématique,Université Libre de Bruxelles and International Solvay Institutes, ULB-Campus Plaine CP231, B-1050 Brussels (Belgium); Blau, Matthias [Albert Einstein Center for Fundamental Physics, University of Bern,Sidlerstrasse 5, 3012 Bern (Switzerland)

    2015-07-10

    We construct several classes of worldvolume effective actions for black holes by integrating out spatial sections of the worldvolume geometry of asymptotically flat black branes. This provides a generalisation of the blackfold approach for higher-dimensional black holes and yields a map between different effective theories, which we exploit by obtaining new hydrodynamic and elastic transport coefficients via simple integrations. Using Euclidean minimal surfaces in order to decouple the fluid dynamics on different sections of the worldvolume, we obtain local effective theories for ultraspinning Myers-Perry branes and helicoidal black branes, described in terms of a stress-energy tensor, particle currents and non-trivial boost vectors. We then study in detail and present novel compact and non-compact geometries for black hole horizons in higher-dimensional asymptotically flat space-time. These include doubly-spinning black rings, black helicoids and helicoidal p-branes as well as helicoidal black rings and helicoidal black tori in D≥6.

  2. DNA packing in chromatine, a manifestation of the Bonnet transformation.

    Science.gov (United States)

    Blum, Z; Lidin, S

    1988-08-01

    The packing of DNA is described using the formalism of differential geometry. Winding of the DNA double helix around the histone 2-5 octamer forming a nucleosome and the condensation of the so-formed bead-on-a-string chromatine aided by histone 1 is interpreted as two consecutive isometric, i.e. Bonnet, transformations. The DNA double helix can be approximated to a helicoid which can be transformed isometrically to a catenoid, an approximation of the nucleosome. Owing to the organization of the histone octamer the extended chromatine takes a helicoidal shape allowing a second Bonnet transformation to consummate the condensation into a chromatine fibre.

  3. Computed tomography to evaluate the association of fragmented heterolog cortical bone and methylmethacrylate to repare segmental bone defect produced in tibia of rabbits; Tomografia computadorizada da matriz ossea mineralizada heterologa fragmentada e metilmetacrilato na reparacao de falhas osseas segmentares produzidas em tibia de coelhos

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, S.H. [Universidade Federal de Sao Paulo (USP), SP (Brazil); Doria, R.G.S. [Universidade Federal de Sao Paulo (USP), SP (Brazil). Faculdade de Zootecnia e Engenharia de Alimentos; Mendonca, F.S.; Santos, M.D.; Moreira, R. [Universidade de Cuiaba, MT (Brazil). Faculdade de Medicina Veterinaria; Simoes, R.S. [Universidade Federal de Sao Paulo (USP), SP (Brazil). Hospital Universitario; Camargo, L.M.; Simoes, M.J. [Universidade Federal de Sao Paulo (USP), SP (Brazil). Escola Paulista de Medicina; Marques, A.T.C. [Universidade de Cuiaba, MT (Brazil). Faculdade de Odontologia

    2012-11-15

    A 6mm segmental defect was performed on the metaphyseal region of the tibia of 12 rabbits and the autoclaved fragmented heterolog cortical bone conserved in glycerin (98%) and methylmethacrylate was used as a bone graft for the reconstruction. The graft was placed in the receptor bed and its integration was evaluated by computed tomography after 30, 60 and 90 days. There was gradual bone graft incorporation in the receptor bed during the time in 100% of the cases. Fragmented cortical bone heterograft and methylmethacrylate was biologically compatible and promotes bone defect reparation without signs of infection, migration and or rejection, featuring a new option of osseous substitute to fill in bone defects. (author)

  4. Contribution of computed tomography in patients with lung metastases of differentiated thyroid carcinoma not apparent on plain radiography who were treated with radioiodine; Contribuicao da tomografia computadorizada em pacientes com metastases pulmonares de carcinoma diferenciado de tireoide nao-aparentes na radiografia e tratados com radioiodo

    Energy Technology Data Exchange (ETDEWEB)

    Rosario, Pedro W.S.; Purisch, Saulo [Santa Casa Belo Horizonte, MG (Brazil). Dep. de Tireoide. Servico de Endocrinologia]. E-mail: pedrorosario@globo.com; Tavares, Wilson C. [Instituto Alpha de Gastroenterologia, Belo Horizonte, MG (Brazil); Barroso, Alvarao L.; Rezende, Leonardo L.; Padrao, Eduardo L. [Santa Casa Belo Horizonte, MG (Brazil). Servico de Medicina Nuclear

    2008-02-15

    Computed tomography (CT or CAT Scan) of the chest is more sensitive than radiography in the detection of lung metastases of differentiated thyroid cancer (DTC), but little information is available regarding the aggregated value of this method. The present study evaluated the response of patients with lung metastases of DTC not apparent on radiography to treatment with {sup 131}I and the value of CT in these cases. Twenty-five patients with lung metastases not apparent on radiography, who initially received 100-200 mCi I{sup 151}, were evaluated and those presenting pulmonary uptake on post-therapy WBS were submitted to a new treatment after 6 to 12 months, and so on. The chance of detection of pulmonary uptake on post-therapy WBS did not differ between patients with negative and positive CT (100% versus 91.5%). Mean serum Tg levels were higher in patients with positive CT (108 ng/ml versus 52 ng/ml). Negative post-therapy WBS was achieved in 82% of patients with positive CT and in 92.3% with negative CT and the cumulative I{sup 131} activity necessary to achieve this outcome did not differ between the two groups (mean = 300 mCi). Stimulated Tg was undetectable in 47% of patients with negative CT at the end of treatment, but in none of the patients whose CT continued to be positive. In patients with elevated Tg, the CT result apparently did not change the indication of therapy or the I{sup 131} activity to be administered. In cases with lung metastases, the persistence of micronodules on CT was associated with the persistence of detectable Tg in patients presenting negative post-therapy WBS. (author)

  5. Frequency of CT studies performed in pediatric patients in the Canary University Hospital in the period 2005-2010; Frecuencia de los estudios de tomografia computerizada a pacientes pediatricos realizados en el hospital universitario de canarias en el periodo 2005-2010

    Energy Technology Data Exchange (ETDEWEB)

    Hdez Armas, O.; Glez Martin, A.; Bethencourt Pana, A.; Catalan Acosta, A.; Hdez Armas, J.

    2011-07-01

    This paper provides data for the number and diversity of computerized tomography scans performed on pediatric patients (<15 years) at the University Hospital of Tenerife (UHT), Canary Islands. The analysis of the frequency and trends of these medical procedures will make comparisons with the medical use of CT in other parts of Spain and the world.

  6. Estudo comparativo do tono muscular na paralisia cerebral tetraparética em crianças com lesões predominantemente corticais ou subcorticais na tomografia computadorizada de crânio Comparative study of muscular tonus in spastic tetraparetic cerebral palsy in children with predominantly cortical and subcortical lesions in computerized tomography of the skull

    Directory of Open Access Journals (Sweden)

    Cristina Iwabe

    2003-09-01

    Full Text Available OBJETIVO: Comparar a distribuição e intensidade do tono muscular na paralisia cerebral tetraparética espástica (PC-T, correlacionando os dados clínicos com a localização da lesão no sistema nervoso central. MÉTODO: Foram incluídas 12 crianças de dois a quatro anos de idade com lesões predominantemente corticais (seis crianças e subcorticais (seis crianças. O tono foi analisado nos membros superiores (MMSS e inferiores (MMII baseado no protocolo de Durigon e Piemonte. RESULTADOS: Não houve diferença significante quanto à intensidade e distribuição de tono em MMSS e MMII nos dois grupos. Comparando os MMSS e MMII de sujeitos do mesmo grupo, os MMII apresentaram mais assimetrias e maior intensidade do tono do que os MMSS. CONCLUSÃO: Neste estudo, crianças com PC devido a lesões predominantemente corticais ou subcorticais apresentam déficit semelhante na modulação de tono, ocasionando distribuição simétrica e homogênea de hipertonia que predomina em MMII.OBJECTIVE: To compare distribution and intensity of muscular tonus in spastic tetraparetic cerebral palsy (CP, correlating the clinical data with lesion location in the central nervous system. METHOD: Twelve children aged two to four years old with predominantly cortical lesions (six children and subcortical lesions (six children were included. The tonus was analyzed in the upper (UULL and lower limbs (LLLL based on Durigon and Piemonte protocol. RESULT: There was no significant difference regarding tonus intensity and distribution in the UULL and LLLL in both groups. Comparing the upper and lower limbs of subjects in the same group, the LLLL presented more asymmetry and higher tonus intensity than the UULL. CONCLUSION: In this study children with CP as a result of predominantly cortical or subcortical lesions present a similar deficit in tonus modulation, causing a symmetric and homogeneous distribution of hypertonicity, which is predominant in the LLLL.

  7. Relationship between radiation dose estimation in patients submitted to abdominal tomography examination and the body mass index; Relacao entre a estimativa de dose de radiacao em pacientes submetidos a exame de tomografia computadorizada do abdomen e o indice de massa corporal

    Energy Technology Data Exchange (ETDEWEB)

    Capaverde, Alexandre da S.; Pimentel, Juliana; Froner, Ana Paula P., E-mail: alexandre.capaverde@acad.pucrs.br, E-mail: juliana.pimentel@pucrs.br, E-mail: ana.froner@pucrs.br [Hospital Sao Lucas (HSL/PUCRS), Porto Alegre, RS (Brazil); Silva, Ana Maria Marques da, E-mail: ana.marques@pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS), Porto Alegre, RS (Brazil). Fac. de Fisica

    2014-07-01

    Because of the radiation dose in computed tomography (CT) is relatively high, it is important to have an estimate of the dose to which the patient is submitted, considering parameters and correction factors, so that the value is closer to the real. The objective of this study is to relate the estimated dose in patients undergoing abdominal CT with BMI (Body Mass Index) groups, considering the specific size of the anatomical region. The work developed in a hospital in Porto Alegre, Brazil, using 16 Siemens Somatom Emotion equipment. We selected 30 adult that underwent to CT of the abdomen in January 2014. Of these, 13 using dose reduction mechanism (Care Dose), (Sample 1) and the rest without this mechanism (Sample 2). Registered weight, height, CTDI{sub vol} (Computed Tomography Dose Index) and anteroposterior and lateral diameter at the umbilicus. BMI and the correction factor for the dose estimates were calculated, according to the specific size of the abdomen. It was determined the percentage change between the CTDI{sub vol} values provided by CT and the value of CTDI{sub vol} after application of the correction factor, plus the average percentage change for each BMI group. The mean percentage change was between 54% and 19% for sample 1 and between 35% and 10% for sample 2, the lowest to highest BMI group. There was a reduction in the medium average percent with the increasing of the BMI groups in both samples. A larger sample of individuals for verification of results is required.

  8. Neutron stimulated emission computed tomography applied to the assessment of calcium deposition due to the presence of microcalcifications associated with breast cancer; Tomografia computadorizada de emissao estimulada por neutrons aplicada para avaliar a deposicao de calcio devido a presenca de microcalcificacoes associadas ao cancer de mama

    Energy Technology Data Exchange (ETDEWEB)

    Viana, Rodrigo S.S.; Yoriyaz, Helio [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, (SP) (Brazil)

    2011-07-01

    In this paper we presented an application of the Neutron Stimulated Emission Computed Tomography (NSECT), which uses a thin beam of fast neutrons to stimulate stable nuclei in a sample, emitting characteristic gamma radiation. The photon energy is unique and it is used to identify the emitting nuclei. This technique was applied for evaluating the calcium isotopic composition changing due to the development of breast microcalcifications. A particular situation was simulated in which clustered microcalcifications were modeled with diameters less than 1.40 mm. In this case, neutron beam breast spectroscopy was successful in detecting the counting changes in the photon emission spectra for energies, which are characteristics of 4{sup 0C}a isotope in a low deposited dose rate. (author)

  9. Real-time three-dimensional echocardiographic left ventricular ejection fraction and volumes assessment: comparison with cardiac computed tomography; Comparacao entre a afericao da fracao de ejecao e dos volumes do ventriculo esquerdo, medidos com ecocardiografia tridimensional em tempo real e com tomografia computadorizada ultra-rapida

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Marcelo L.C.; Nomura, Cesar H.; Tranchesi Junior, Bernardino; Oliveira, Wercules A. de; Naccarato, Gustavo; Serpa, Bruna S.; Cury, Alexandre; Passos, Rodrigo B.D.; Nobrega, Marcel V. da; Funari, Marcelo B.G.; Pfefermam, Abhaham; Makdisse, Marcia; Fischer, Claudio H.; Morhy, Samira S., E-mail: luiz766@terra.com.br [Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil)

    2008-10-15

    Background and objective: Few studies addressed the comparison between real-time 3D echocardiography (RT3DE) and cardiac computed tomography (CCT) concerning left ventricular ejection fraction and volumes assessment. We sought to compare both techniques regarding left ventricle (LV) ejection fraction function and volumes analysis. Methods: we studied by RT3DE (Philips IE 33, And, MA, USA) and by CCT (Toshiba, 64-slice, Otawara, Japan) 41 consecutive patients (29 males, 58 ± 11 yrs). We analysed by both techniques LVEF, LVEDV, LVESV. RT3DE and CCT data were compared by coefficients of determination (r: Pearson), Bland and Altman test and linear regression, 95% CI. Results: RT3DE data: LVEF ranged from 56.7 to 78.9 % (65.3 + 5.7 ); LVEDV ranged from 49.6 to 178.2 (88 + 27.5) mL; LVESV from 11.4 to 78 ( 33.9 + 13.7) mL. CCT data: LVEF ranged from 53 to 86 % (67.3 + 7.9 ); LVEDV ranged from 51 to 186 (106.4 + 30.7) mL; LVESV from 7 to 72 ( 35.1 + 13.8) mL. Correlations relative to RT3DE and CCT were: LVEF (r: 0. 7877, p<0.0001, 95 % CI 0.6327 to 0.8853 ); LVEDV (r:0.7671, p<0.0001, 95 % CI 0.5974 to 0.8745); LVESV (r: 0.8121, p<0.0001, 95 % CI 0.6659 to 0.8957). Conclusions: it was observed adequate correlation between real-time 3D echocardiography and cardiac computed tomography concerning ejection fraction and volumes assessment. (author)

  10. Juvenile nasopharyngeal angiofibroma - study of the tumor extension and vascularization through computerized tomography (CT) scan and angiography and the patient's age; Nasoangiofibroma juvenil - estudo da extensao e vascularizacao do tumor pela tomografia computadorizada e angiografia, e da idade do paciente

    Energy Technology Data Exchange (ETDEWEB)

    Sennes, Luiz Ubirajara

    1997-07-01

    The juvenile nasopharyngeal angiofibroma is a rare benign tumor that affects male adolescents. It is a fibro-vascular tumor with an exuberant intra tumor blood flow and irrigated by several arteries. It originates from the lateral and posterior region of the nasal cavity and, due to its characteristic multidirectional growth, widely affects the paranasal sinuses and skull base, sometimes invading the cranial fossa or the cheek. The determinant factors of its growth and vascularisation are unknown. Attempting to clarify them, 33 patients from the University of Sao Paulo Medicine were studied from 1983 to 1995, with complete history and radiological documentation (CT scan and angiography), as well as with histological confirmation of the diagnosis. In order to take only tumors with natural evolution, patients with recidivant tumor and those already submitted to any previous treatment were excluded. The parameters evaluate were: patient age and tumor extension (by classification, degree of invasion and number of compromised sites in CT scan) and vascularisation (by number and degree of participation of bilateral arteries in angiography). The se data were tabled and correlated one with each other. (author)

  11. Ablation of burned skin with ultra-short pulses laser to promote healing: evaluation by optical coherence tomography, histology, {mu}ATR-FTIR and Nonlinear Microscopy; Ablacao de pele queimada com laser de pulsos ultra-curtos para promocao da cicatrizacao: avaliacao por tomografia por coerencia optica, histologia, {mu}ATR-FTIR e microscopia nao-linear

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Moises Oliveira dos

    2012-07-01

    Burns cause changes in the anatomical structure of the skin associated with trauma. The severity of the burn injury is divided into first, second and third-degree burns. The third-degree burns have been a major focus of research in search of more conservative treatments and faster results in repair for a functional and cosmetically acceptable. The conventional treatment is the use of topical natural or synthetic skin graft. An alternative therapy is the laser ablation process for burned tissue necrosis removal due to the no mechanical contact, fast application and access to difficult areas. The purpose of this study is to evaluate the feasibility of using high intensity femtosecond lasers as an adjunct treatment of burned patients. For this study, 65 Wistar rats were divided into groups of five animals: healthy skin, burned skin, two types of treatment (surgical debridement or femtosecond laser ablation) and four different times in the healing process monitoring. Three regions of the back of the animals were exposed to steam source causing third-degree burn. On the third day after the burn, one of the regions was ablated with high intensity ultrashort laser pulses ({lambda} = 785 nm, 90 fs, 2 kHz and 10 {mu}J/ pulse), the other received surgical debridement, and the last was considered the burn control. The regions were analyzed by optical coherence tomography (OCT), histology, attenuated total reflectance infrared spectroscopy using Fourier transform ({mu}-ATR-FTIR), two-photon excitation fluorescence microscopy (TPEFM) and second harmonic generation technique (SHG) on days 3, 5, 7 and 14 pos-treatments. The results showed that with the laser irradiation conditions used it was possible to remove debris from third degree burn. The techniques used to characterize the tissue allowed to verify that all treatments promoted wound healing. On the fourteenth day, the regeneration curve showed that the attenuation coefficient of laser ablated tissue converges to the values of healthy skin, but collagen fibers have not yet reached the same organization of those in the healthy skin. (author)

  12. Pilot project for the establishment of diagnosis reference level in pediatric computerized tomography in Rio de Janeiro city, RJ, Brazil; Projeto piloto para o estabelecimento de niveis de referencia de diagnostico em tomografia computadorizada pediatrica no municipio do Rio de Janeiro, RJ, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Jesus, Fillipe Machado de

    2014-08-01

    Computed tomography (CT) is an important method of diagnostic imaging has been widely used around the world. However, this important diagnostic tool has led to a considerable increase in the frequency of examinations, often without proper clinical justification. Consequently, CT is one of the diagnostic procedures that contributes most to the collective dose. Scientific studies show that the concern in pediatric procedures should be even higher. Despite the fact that these patients have a higher radiosensitivity and a higher life expectancy, the protocols of the examinations are not optimized and adult protocols are applied. Moreover, a recent study performed in the United States showed that one third of the examinations was not justified. The aim of this study was to conduct a pilot study of dose indicators in pediatric CT in four hospitals, in order to verify the feasibility of the diagnostic reference levels establishment for the county of Rio de Janeiro. The dose descriptors were estimated from the beam dosimetry by applying the protocols used in each examination. The total patient sample included 358 children of different age groups. The results observed in examinations of whole trunk (routine chest, upper abdomen and pelvis) and upper abdomen in Institution A, for patients aged 5-10 years, indicated that the mAs values used were not properly selected for patients' body mass index, presenting however, conformity with UK reference levels. In the case of head CT scans and routine chest CT scans in Institution B, although patients aged 5-10 years have shown conformity with UK reference levels, the kV and mAs values used, in some examinations, were also inappropriate for the patient characteristics. Similar result was observed in examinations of head and high resolution chest for patients neonates, in Institution D. For head and routine chest examinations of 1-5 years' age group, was Institution B that showed the lowest DLP values. This result was due to the lowest CTDlyol values found therein. Comparisons of DLP values among institutions, for each age group in each kind of examination, also allowed observe a mean difference of 2248% in the Institution A's values in relation to the Institution D's values, for high resolution chest examinations of the 5-10 years age group. These results indicate that few efforts are being devoted to radiation protection in pediatric computed tomography, there is a high potential for optimization and that to establish tomographic good practices is essential the determination of diagnostic reference levels. (author)

  13. Retrospective study of computed tomography of nasal cavity in small animal at FMVZ - UNESP, Botucatu, and correlation of changes with cytological and/or histopathological exams; Estudo retrospectivo de tomografia computadorizada da cavidade nasal em pequenos animais na FMVZ - UNESP, Botucatu, e correlacao das alteracoes com os exames citologico e/ou histopatologico

    Energy Technology Data Exchange (ETDEWEB)

    Belotta, Alexandra Frey; Inamassu, Leticia Rocha; Mamprim, Maria Jaqueline; Machado, Vania Maria de Vasconcelos; Vulcano, Luiz Carlos, E-mail: a_fbelotta@yahoo.com.br [Universidade Estadual Paulista Julio de Mesquita Filho (FMVZ/UNESP), Botucatu, SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia. Dept. de Reproducao Animal e Radiologia Veterinaria; Zardo, Karen Maciel

    2012-07-01

    It was conducted a retrospective study of computed tomography (CT) scans of nasal cavity in small animal at this institution during the period of April 2007 through June 2012. In total, 47 CT scans were performed during the period and, of these, only 25 underwent additional exams (cytological and/or histopathological). 20 exams suggested a diagnosis, 4 were inconclusive and one had no change. A correlation was made between tomographic findings and cytological/histopathological diagnosis providing an accurate assessment of neoplastic versus non-neoplastic disease. (author)

  14. Prevalence of soft tissue calcifications in cone beam computed tomography images of the mandible = Prevalência de calcificações em tecido mole na região mandibular avaliadas por dois sistemas de tomografia computadorizada por feixe cônico

    Directory of Open Access Journals (Sweden)

    Nunes, Leiliane Ferreira da Silva

    2011-01-01

    Conclusão: Os sistemas de TCFC avaliados mostraram-se ferramentas valiosas na identificação de calcificações em tecido mole, embora as imagens não permitam exata localização destas calcificações

  15. Comparative study of muscular tonus in spastic tetra paretic cerebral palsy in children with predominantly cortical and subcortical lesions in computerized tomography of the skull; Estudo comparativo do tono muscular na paralisia cerebral tetraparetica em criancas com lesoes predominantemente corticais ou subcorticais na tomografia computadorizada de cranio

    Energy Technology Data Exchange (ETDEWEB)

    Iwabe, Cristina [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Neurologia; Piovesana, Ana Maria Sedrez Gonzaga [Universidade Estadual de Campinas, SP (Brazil). Ambulatorio Multidisciplinar de Paralisia Cerebral e Neurologia Infantil

    2003-09-01

    The objective was to compare distribution and intensity of muscular tonus in spastic tetra paretic cerebral palsy (CP), correlating the clinical data with lesion location in the central nervous system. Twelve children aged two to four years old with predominantly cortical lesions (six children) and subcortical lesions (six children) were included. The tonus was analyzed in the upper (UULL) and lower limbs (LLLL) based on Durigon and Piemonte protocol. The result showed that there was no significant difference regarding tonus intensity and distribution in the UULL and LLLL in both groups. Comparing the upper and lower limbs of subjects in the same group, the LLLL presented more asymmetry and higher tonus intensity than the UULL. It was concluded that in this study children with CP as a result of predominantly cortical or subcortical lesions present a similar deficit in tonus modulation, causing a symmetric and homogeneous distribution of hypertonicity, which is predominant in the LLLL. (author)

  16. Influence of ASIR (Adaptative Statistical Iterative Reconstruction) variation in the image noise of computerized tomography for high voltage; Influência da variação do ASIR (Adaptative Statistical Iterative Reconstruction) no ruído da imagem de tomografia computadorizada para altas tensões

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, L.M.M.; Pereira, W.B.R.; Vieira, J.G.; Lamounier, C.S.; Gonçalves, D.A.; Carvalho, G.N.P.; Santana, P.C., E-mail: lucasmoacir2010@hotmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Oliveira, P.M.C.; Reis, L.P., E-mail: paulomarcio2000@gmail.com [Centro de Desenvolvimento de Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    Computed tomography had great advances in the equipment used in the diagnostic practice, directly influencing the levels of radiation for the patient. It is essential to optimize techniques that must be employed to comply with the ALARA (As Low As Reasonably Achievable) principle of radioprotection. The relationship of ASIR (Adaptive Statistical Iterative Reconstruction) with image noise was studied. Central images of a homogeneous water simulator were obtained in a 20 mm scan using a 64-channel Lightspeed VCT tomograph of General Electric in helical acquisitions with a rotation time of 0.5 seconds, Pitch 0.984: 1, and thickness of cut 0.625 mm. All these constant parameters varying the voltage in two distinct values: 120 and 140 kV with use of the automatic current by the CAE (Automatic Exposure Control), ranging from 50 to 675 mA (120 kV) and from 50 to 610 mA (140kV), minimum and maximum values, respectively allowed for each voltage. Image noise was determined through ImageJ free software. The analysis of the obtained data compared the percentage variation of the noise in the image based on the ASIR value of 10%, concluding that there is a variation of approximately 50% when compared to the values of ASIR (100%) in both tensions. Dose evaluation is required in future studies to better utilize the relationship between dose and image quality.

  17. Geostatistical Modelling of the Travertine Formation Associated with the Alicun de las Torres Thermal System by Using Electrical Tomography and Porosity Data; Modelizacion mediante Tecnicas Geoestadisticas de la Formacion de Trevertinos Asociada al Sistema Termal de Alicun de las Torres a partir de Datos de Tomografia Electrica y Porosidad

    Energy Technology Data Exchange (ETDEWEB)

    Prado Perez, A. J.; Aracil, E.; Perez del Villar, L.

    2010-11-17

    In the framework of a Singular Strategic Project entitled: Advanced Technologies of Carbon, Capture and Storage (CCS)1', supported by the MICINN (Spain) and the FEDER founds (EU), specifically in the Carbon Storage Task, a comprehensive study on the CO{sub 2} leakage as DIG (Dissolved Inorganic Carbon) in the Alicun de Las Torres (Prov. of Granada) natural analogue thermal system was envisaged. This analogous system is characterised by the presence of a very important travertine formation, which can be considered as a permanent and stable sink for CO{sub 2}. Consequently, the estimation of the travertine mass has been a main objective of this investigation. For that, data from two complementary electrical tomography campaigns, previously treated by a powerful geostatistical tool, have been used, as well as the porosity average value of this travertine and the calcite density. Besides this, the statistical methodology applied has also allowed the establishment of a 3-D model of the travertine formation, displaying the geological contact between this formation and the underlying materials, as well as the contacts among the three units forming the travertine formation. (Author) 23 refs.

  18. Development of an optimized algorithm for the characterization of microflow using speckle patterns present in optical coherence tomography signal; Desenvolvimento de um algoritimo otimizado para caracterizacao de fluxos microfluidicos utilizando padroes de speckle presentes no sinal de tomografia por coerencia optica

    Energy Technology Data Exchange (ETDEWEB)

    Pretto, Lucas Ramos de

    2015-07-01

    This work discusses the Optical Coherence Tomography system (OCT) and its application to the microfluidics area. To this end, physical characterization of microfluidic circuits were performed using 3D (three-dimensional) models constructed from OCT images of such circuits. The technique was thus evaluated as a potential tool to aid in the inspection of microchannels. Going further, this work paper studies and develops analytical techniques for microfluidic flow, in particular techniques based on speckle pattern. In the first instance, existing methods were studied and improved, such as Speckle Variance - OCT, where a gain of 31% was obtained in processing time. Other methods, such as LASCA (Laser Speckle Contrast Analysis), based on speckle autocorrelation, are adapted to OCT images. Derived from LASCA, the developed analysis technique based on intensity autocorrelation motivated the development of a custom OCT system as well as an optimized acquisition software, with a sampling rate of 8 kHz. The proposed method was, then, able to distinguish different flow rates, and limits of detection were tested, proving its feasibility for implementation on Brownian motion analysis and flow rates below 10 μl/min. (author)

  19. Proposals for implementation of methodological aspects in the use of {sup 18}F-FDG in the Positron Emission Tomography; Propostas de implementações de aspectos metodológicos na utilização do {sup 18}F-FDG na Tomografia Por Emissão de Pósitron

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Cássio Miri

    2013-07-01

    This work covered three objectives: to evaluate and implement methods for in vivo internal occupational monitoring of individuals involved during the {sup 18}F-FDG process production; to suggest a national Diagnostic Reference Level (DRL) for {sup 18}F-FDGPET oncologic procedures; and to obtain the 'Recovery Coefficients' (RCs) factors used to correct the radiopharmaceutical uptake in region of interest for a better quantification and evaluation of images. The methodology of internal monitoring was implemented in the radiopharmaceuticals production centers of Nuclear Technology Development Center (CDTN) in Belo Horizonte - MG and the Nuclear Science Regional Center, North-East (CRCN-NE) in Recife, PE, Brazil. The results demonstrated that the developed methodology was efficient to evaluate {sup 18}F-FDG incorporations in both centers; additionally, the methodology showed that there was possibility of {sup 18}F incorporation in the form of {sup 18}F-FDG during non-routine actions performed in the radiopharmaceutical production process. DRLs were suggested based on a questionnaire that was used for the survey of {sup 18}F-FDG administered activity in 72 Brazilian clinics currently licensed by the National Nuclear Energy Commission (CNEN). The results reported by 41 (57%) of the {sup 18}F-FDG-PET clinics showed variations up to 100% in the administered activities among clinics for the same procedure. The calculated DRL from the third quartile was 5.54 MBq/kg or 387.7 MBq (for a 70 kg standard patient). For image analysis, two phantoms were used for obtaining the RCs, the NEMA/IEC Body Phantom, which has spherical capture areas and the modified Jaszczak, which has cylindrical capitation capture areas. Both phantoms were tested for different lesion:BG activity ratios, in the amount of 4:1 and 10:1; for different acquisition time. RCs obtained according to NEMA and IEC standards were applied to the SUVmax and SUVmed semi quantification tools. Values of SUVmed corrected by RCs presented satisfactory results with the smallest differences (1.1 a 6.7%) in relation to the SUVreference values for both phantoms; even for different adopted acquisition time and different capture area geometries (spherical and cylindrical). However, it did not occur with corrected SUVmax values. This work contributed to a better knowledge of the {sup 18F} FDG- PET technique pointing mishaps and possible methodologies to repair them with the primary intention to cooperate for the radiological safety of occupational exposed individuals and patient's health. (author)

  20. Computerized tomography with X-rays: an instrument in the analysis physico-chemical between formations and drilling fluids interactions; Tomografia computadorizada com raios-X: uma ferramenta na analise das interacoes fisico-quimicas entre as formacoes rochosas e fluidos de perfuracao

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Marcus Vinicius Cavalcante

    1998-12-31

    In this study it is demonstrated the applicability of the Computerized Tomography technique with x-rays to evaluate the reactivity degree between various drilling fluids and argillaceous sediments (Shales and Sandstones). The research has been conducted in the Rock-Fluid Interaction Pressure Simulator (RFIPS), where the possible physico-chemical alterations can be observed through successive tomography images, which are obtained during the flow of the fluid through the samples. In addition, it was noticed the formation of mud cake in Berea Sandstones samples in the RFIPS, though the Computerized Tomography with X-rays, when utilizing drilling fluids weighted with the baryte. (author) 35 refs., 38 figs., 5 tabs.

  1. Computerized tomography with X-rays: an instrument in the analysis physico-chemical between formations and drilling fluids interactions; Tomografia computadorizada com raios-X: uma ferramenta na analise das interacoes fisico-quimicas entre as formacoes rochosas e fluidos de perfuracao

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Marcus Vinicius Cavalcante

    1999-12-31

    In this study it is demonstrated the applicability of the Computerized Tomography technique with x-rays to evaluate the reactivity degree between various drilling fluids and argillaceous sediments (Shales and Sandstones). The research has been conducted in the Rock-Fluid Interaction Pressure Simulator (RFIPS), where the possible physico-chemical alterations can be observed through successive tomography images, which are obtained during the flow of the fluid through the samples. In addition, it was noticed the formation of mud cake in Berea Sandstones samples in the RFIPS, though the Computerized Tomography with X-rays, when utilizing drilling fluids weighted with the baryte. (author) 35 refs., 38 figs., 5 tabs.

  2. Determination of the dose equivalent Hp(0.07) in hands of occupationally exposed personnel in the practice of proton emission tomography (PET/CT); Determinacion de la dosis equivalente Hp(0.07) en manos de trabajadores ocupacionalmente expuestos en la practica de Tomografia por Emision de Positrones (PET/CT)

    Energy Technology Data Exchange (ETDEWEB)

    Lea, D. [Servicio de Radiofisica Sanitaria, Unidad de Tecnologia Nuclear, Instituto Venezolano de Investigaciones Cientificas, Ministerio de Ciencia y Tecnologia, Km 11 Carretera Panamerican, Altos del Pipe, Caracas (Venezuela); Ruiz, N.; Esteves, L. [Centro Diagnostico Docente Las Mercedes, Calle Paris cruce con calle Caroni, Edif. CDD, Las Mercedes, Caracas (Venezuela)]. e-mail: dlea@ivic.ve

    2006-07-01

    In Venezuela recently it was implanted the Positron Emission Tomography technique (PET) with the perspective of implanting it at national level. Even when in our country practices it of nuclear medicine it exists from early of 70, there is not experience in the determination of the occupational doses by exposure to the external radiation in hands. By this reason, a concern exists in the workers of the centers of nuclear medicine where it is practiced the Positron Emission Tomography technique. In absence of the TLD dosimetry to measure dose in hands in our country, measurements of the dose equivalent of the workers of the PET national reference center were made, using a detector of hands type diode. It was determined the dose in hands in terms of dose equivalent Hp(0.07) in two work positions, that is: the corresponding to the transfer of the receiving vial of ({sup 18}F) FDG to the shield, quality control and uni doses division. The second work position corresponds the person in charge of administering, via intravenous, the ({sup 18}F) FDG. In this work it realizes the dose equivalent in hands Hp(0.07) measures in each one of the work positions before described by daily production. The informed doses correspond to a total average produced activity of 20.4 GBq (550 mCi). The results of the measurements in terms of dose equivalent in hands Hp(0.07) correspond to 2.1 {+-} 20% mSv in the work position of division and 0.4 {+-} 10% mSv in the position of injection of the radioactive material. At short term this foreseen until 4 productions per week, what means an annual dose equivalent Hp(0.07) in hands of 400 mSv approximately, without taking into account abnormal situations as its are spills of the ({sup 18}F) FDG in the work place. This work is the starting point so that the regulatory authority settles down, in Venezuela, dose restrictions in the PET practices and implant, in the centers of nuclear medicine, an optimization politics of this practice in conformity with the ALARA principle. (Author)

  3. {sup 99m}Tc sestamibi cardiac tomography and dobutamine echocardiography in the identification of reversible left ventricular dysfunction in patients with acute myocardial infarction; Tomografia cardiaca con {sup 99m}Tc sestamibi ed ecocardiografia con dobutamina nell'identificazione della disfunzione ventricolare sinistra reversibile nei pazienti con infarto acuto del miocardio

    Energy Technology Data Exchange (ETDEWEB)

    Gisonni, P.; Cuocolo, A.; Spinelli, L.; Acampa, W.; Florimonte, L.; Nicolai, E.; Petretta, M.; Sodano, A. [Naples Univ. Federico 2. (Italy). Centro per la Medicina Nucleare del Consiglio Nazionale delle Ricerche. Dipt. di Scienze Biomorfologiche e Funzionali

    1999-04-01

    The authors investigated the role of technetium-99m ({sup 99m}Tc) sestamibi cardiac imaging and dobutamine echocardiography in detecting myocardial viability early after acute myocardial infarction. [Italian] La presenza di tessuto miocardico ibernato o stordito contribuisce alla genesi della disfunzione ventricolare sinistra nei pazienti con infarto del miocardio. L'identificazione del miocardio malfunzionante ma ancora vitale ha particolare rilevanza nel predire il recupero della funzione ventricolare in seguito a interventi di rivascolarizzazione coronarica. In questo studio e' stato valutato il ruolo della scintigrafia con tecnezio-99m ({sup 99m}Tc) sestamibi e dell'ecocardiografia con dobutamina nell'identificazione del miocardio vitale dopo infarto acuto del miocardio.

  4. Tomografia computadorizada na análise dos padrões de calcificações nos tumores ósseos da bacia em pediatria: nova abordagem Computed tomography in the analysis of calcification patterns in pediatric bone tumors of the hip: a new approach

    Directory of Open Access Journals (Sweden)

    Gabriel Antônio de Oliveira

    2006-12-01

    Full Text Available OBJETIVO: No grupo pediátrico, o diagnóstico radiológico dos tumores dos ossos ilíacos, ísquios e púbis apresenta dificuldades e peculiaridades próprias, mas a literatura revisada não trata especificamente desse tema. Este trabalho pretende investigar a existência de padrões radiológicos confiáveis para o diagnóstico diferencial desses tumores. MATERIAIS E MÉTODOS: Foram revistos os achados radiológicos de tumores dos ossos do quadril em dez pacientes com idades entre 8 e 19 anos. RESULTADOS: Reação óssea (esclerose ou lise, reação periosteal (lamelar em camada única, múltiplas camadas ou radial, extensão do tumor no osso e grau de invasão das partes moles revelaram baixa especificidade. As calcificações nas partes moles, consideradas em conjunto, foram inespecíficas. Contudo, separando as próximas do osso comprometido, que apresentam formas e tamanhos variados - padrão I -, daquelas afastadas do osso, finas e amorfas - padrão II -, observamos que o padrão I foi totalmente inespecífico e o padrão II foi identificado nos três casos de osteossarcoma (100% e em apenas um dos casos de Ewing (16,6%. CONCLUSÃO: Neste material, as calcificações padrão II revelaram sensibilidade de 100% e especificidade de 90% para osteossarcoma. Contudo, sua importância pode não se limitar ao diagnóstico radiológico. As calcificações padrão II indicam, provavelmente, os sítios ideais para biópsia.OBJECTIVE: In the pediatric group, the radiological diagnosis of bone tumors of the hip is difficult and presents some peculiarities, but reviewed literature does not approach this specific problem. The objective of the present study was to investigate the existence of reliable radiological patterns for the differential diagnosis of these tumors. MATERIALS AND METHODS: Radiological findings of bone tumors of the hip in ten patients in the age range between 8 and 19 years have been reviewed. RESULTS: Bone reaction (sclerosis or lysis, periosteal reaction (lamellar with single or multiple layers, or radial, tumor extent in the bone and level of soft tissues invasion have presented low specificity. Soft tissue calcifications, when considered as a whole, were non-specific. However, when those calcifications with varied shapes and sizes, nearby the affected bone (pattern I were separated from those, thin and amorphous, away from the bone (pattern II, we have observed that the pattern I was totally non-specific, and the pattern II was found in the three cases of osteosarcoma (100% and in only one case of Ewing's sarcoma (16.6%. CONCLUSION: In the present study, pattern II calcifications have shown a 100% sensitivity and 90% specificity for osteosarcoma. However, their importance may be not limited to the radiological diagnosis. Pattern II calcifications indicate probably ideal sites for biopsy.

  5. 10 años de la secuenciación del genoma humano: Encuentro entre el imaginario y la realidad

    Directory of Open Access Journals (Sweden)

    María Teresa Reguero Reza

    2013-01-01

    Full Text Available Lejano parece en año de 1953 cuando se publica en Nature un artículo sobre la estructura helicoidal de ADN, propuesta por dos investigadores, el británico Francis Crick y el estadounidense James Watson, lo que constituyó la piedra angular de los procesos de secuenciación.

  6. Maurer-cartan forms for fields on surfaces

    DEFF Research Database (Denmark)

    Piuze, Emmanuel; Sporring, Jon; Siddiqi, Kaleem

    2015-01-01

    We study the space of first order models of smooth frame fields using the method of moving frames. By exploiting the Maurer-Cartan matrix of connection forms we develop geometrical embeddings for frame fields which lie on spherical, ellipsoidal and generalized helicoid surfaces. We design methods...

  7. Kinks and vortex-twister dynamics in type-II superconductors

    Science.gov (United States)

    D'Anna, G.; Benoit, W.; Sémoroz, A.; Berseth, V.

    1997-02-01

    We report magneto-optical observations of moving helicoidal vortex structures in high purity YBa 2Cu 3O 7-δ single cyrstals. We found that the dynamics of these ‘vortex-twisters’ is mainly controlled by localized instabilities (kinks) which stream along the helices. The kinks allow the motion of the twisters, or the annihilation of twisters with opposite chirality.

  8. Morse potential in DNA molecule – An experiment proposal

    Indian Academy of Sciences (India)

    2012-07-27

    Jul 27, 2012 ... We rely on the helicoidal Peyrard-Bishop model for DNA dynamics. Interaction between nucleotides at a same site belonging to different strands is modelled by a Morse potential energy. This potential depends on two parameters that are different for AT and CG pairs, which is a possible source for ...

  9. Unmanned Systems: A Lab Based Robotic Arm for Grasping Phase II

    Science.gov (United States)

    2016-12-01

    a Hand Operator. ............................................... 38  Figure 31.  Top View of the Leap Motion Controller Tracking Points During...During Helicoid Motion of a Hand Operator. ............................................... 40  Figure 33.  Top View of the Leap Motion Controller...in a controlled lab environment for different predetermined tasks under a glove sensor controller. In his research, the main goal was to integrate

  10. Moving frames for heart fiber geometry

    DEFF Research Database (Denmark)

    Piuze, Emmanuel; Sporring, Jon; Siddiqi, Kaleem

    2013-01-01

    fibers is central to our understanding of normal heart function. Motivated by a recent abstraction by Savadjiev et al. of heart wall fibers into generalized helicoid minimal surfaces, this paper develops an extension based on differential forms. The key idea is to use Maurer-Cartan’s method of moving...

  11. Dissecção da artéria basilar: relato de caso

    Directory of Open Access Journals (Sweden)

    TOGNOLA WALDIR ANTONIO

    2000-01-01

    Full Text Available Relato de um caso de dissecção da artéria basilar, documentado com neuroimagem (tomografia computadorizada do crânio, ressonância magnética e angiografia digital com subtração de imagem.

  12. Radiation dose to the patient and the radiologist while performing on chest computed tomography: a program of early diagnosis of lung cancer, biopsy and treatment simulation guided radiation oncologist breast cancer; Dosis de radiacion al paciente y al radiologo durante la realizacion de tomografia computarizada en torax: progrma de diagnostico precoz del cancer de pulmon, biopsia guiada y simulacion del tratamiento oncologo radioterapico del cancer de mama

    Energy Technology Data Exchange (ETDEWEB)

    Pastor Sanchis, V.; Martinez Sanchez, J. M.; Palma Copete, J. D.; Crispin Contreras, V.; Casal Zamorano, E.; Dolores Alemany, V. de los; Gonzalez Perez, V.; Gimeno Olmo, J.; Guardino de la Flor, C.

    2011-07-01

    In this paper we determine the equivalent dose received by the operator and patient lung biopsies using thermoluminescence dosimeters, are established recommendations that this dose is as low as possible. It also reviews the acquisition protocols in both CT scans in early diagnosis program cited as the acquisition of CT for treatment planning dosimetric radiation oncologist in breast cancer.

  13. Analysis of Tandem curves by set of cylindrical absorber layers and ionization chamber type pencil for evaluation of HVL in computerized tomography; Análise de curvas Tandem obtidas por meio de conjuntos de capas absorvedoras cilíndricas e câmara de ionização do tipo lápis para avaliação de CSR em Tomografia Computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Fontes, Ladyjane Pereira; Potiens, Maria da Penha Albuquerque, E-mail: lpfontes@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    A Tandem system consists of the use of different energy dependent dosimeters, where the ratio of the responses of the calibration curves to energy provides the effective energy of the beam. The efficiency of this system is related to the uncertainties inherent in the dosimeter used and the degree of energy dependence of each set. The greater the slope of the Tandem curve the better will be the identification of values close to HVL making the system useful. In this work, the Tandem system consists of ionization chamber of the pencil type and cylindrical absorber layers of materials with different energetic dependencies, for application in computed tomography. (author)

  14. Efeito da temperatura no crescimento micelial e patogenicidade de Pythium spp. que ocorrem em alface hidropônica Temperature effects on mycelial growth and pathogenicity of Pythium spp. occuring in hydroponic lettuce

    Directory of Open Access Journals (Sweden)

    Liliane De Diana Teixeira

    2006-09-01

    Full Text Available Doze isolados de Pythium foram obtidos de raízes de alface cultivada em sistemas hidropônicos comerciais, apresentando ou não sintomas de apodrecimento. Três desses isolados foram identificados como Pythium helicoides Drechsler (H1, H2 e H3, cinco como pertencentes ao grupo F (F1 a F5 e quatro ao grupo T (T1 a T4 de Pythium. A identificação das espécies foi realizada baseando-se nas características morfológicas. O efeito da temperatura (10, 15, 18, 21, 24, 27, 30, 37 e 40ºC sobre o crescimento micelial foi determinado para todos os isolados. As temperaturas mínima e máxima, estimadas pela função beta generalizada, variaram de 3,5 a 10ºC e de 40 a 40,7ºC, respectivamente. A temperatura ótima foi de 24 a 37ºC para P. helicoides, de 25 a 35ºC para o isolado F4 e de 21 a 30ºC para os demais isolados. A patogenicidade e a agressividade dos isolados foram avaliadas, inoculando-se sementes de alface cv. Verônica, semeadas em ágar-água, a 21 e 30ºC. A 30ºC, os isolados de P. helicoides foram notadamente os mais agressivos, ocasionando 100 % de mortalidade das sementes logo após sua germinação. A 21ºC, todos os isolados induziram subdesenvolvimento de plântulas, acompanhado ou não de necrose dos tecidos radiculares. Trata-se do primeiro relato de P. helicoides para o Brasil e a primeira referência mundial da espécie em hidroponia.Twelve Pythium isolates were obtained from lettuce roots grown hydroponically in commercial systems, showing or not symptoms of rotting. Three of them were identified as P. helicoides (H1, H2 and H3, whereas five were shown to belong to group F (F1-F5 and four to group T (T1-T4 of Pythium. The identification of the species was based on morphological characteristics. The effect of temperature (10, 15, 18, 21, 24, 27, 30, 37 and 40ºC on the mycelial growth was determined for all isolates. Minimum and maximum temperatures, estimated by the generalized beta function, varied from 3.5 to 10ºC and 40

  15. Propagation of thermal neutrons in mock-up screw-shaped steel elements with water protection; Propagation des neutrons thermiques dans des fausses cartouches d'acier en helice dans une protection d'eau. Programme tournesol 3

    Energy Technology Data Exchange (ETDEWEB)

    Devillers, C L; Lanore, J M [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-07-01

    This report treats the streaming of thermal neutrons in a cylindrical duct in light water. The duct contains a spiral iron shield. Transmission and reflection matrices are used to describe the probabilities for the thermal neutrons to be absorbed or to be scattered on the surfaces. The neutron paths across the void are represented by geometrical matrices. The numerical resolution is performed by the Monte-Carlo method. (authors) [French] Dans ce rapport on traite un probleme de fuites de neutrons thermiques dans un canal cylindrique plonge dans l'eau et obture par un ecran helicoidal en acier. On utilise des matrices de transmission-reflexion pour decrire les probabilites d'absorption et de diffusion des neutrons sur les parois et l'helicoide et des matrices de correspondance geometrique pour representer la propagation dans le vide. La resolution numerique se fait par une methode de Monte-Carlo. (auteur)

  16. Biomimetic Structural Materials: Inspiration from Design and Assembly.

    Science.gov (United States)

    Yaraghi, Nicholas A; Kisailus, David

    2018-04-20

    Nature assembles weak organic and inorganic constituents into sophisticated hierarchical structures, forming structural composites that demonstrate impressive combinations of strength and toughness. Two such composites are the nacre structure forming the inner layer of many mollusk shells, whose brick-and-mortar architecture has been the gold standard for biomimetic composites, and the cuticle forming the arthropod exoskeleton, whose helicoidal fiber-reinforced architecture has only recently attracted interest for structural biomimetics. In this review, we detail recent biomimetic efforts for the fabrication of strong and tough composite materials possessing the brick-and-mortar and helicoidal architectures. Techniques discussed for the fabrication of nacre- and cuticle-mimetic structures include freeze casting, layer-by-layer deposition, spray deposition, magnetically assisted slip casting, fiber-reinforced composite processing, additive manufacturing, and cholesteric self-assembly. Advantages and limitations to these processes are discussed, as well as the future outlook on the biomimetic landscape for structural composite materials.

  17. Biomimetic Structural Materials: Inspiration from Design and Assembly

    Science.gov (United States)

    Yaraghi, Nicholas A.; Kisailus, David

    2018-04-01

    Nature assembles weak organic and inorganic constituents into sophisticated hierarchical structures, forming structural composites that demonstrate impressive combinations of strength and toughness. Two such composites are the nacre structure forming the inner layer of many mollusk shells, whose brick-and-mortar architecture has been the gold standard for biomimetic composites, and the cuticle forming the arthropod exoskeleton, whose helicoidal fiber-reinforced architecture has only recently attracted interest for structural biomimetics. In this review, we detail recent biomimetic efforts for the fabrication of strong and tough composite materials possessing the brick-and-mortar and helicoidal architectures. Techniques discussed for the fabrication of nacre- and cuticle-mimetic structures include freeze casting, layer-by-layer deposition, spray deposition, magnetically assisted slip casting, fiber-reinforced composite processing, additive manufacturing, and cholesteric self-assembly. Advantages and limitations to these processes are discussed, as well as the future outlook on the biomimetic landscape for structural composite materials.

  18. Aortocaval fistula: an infrequent complication of aneurysm of the abdominal aorta; Fistula aortocava: complicacion infrecuente tras rotura de aneurisma de aorta abdominal

    Energy Technology Data Exchange (ETDEWEB)

    Alpera, R.; Ardoy, F.; Gallego, J. A.

    2002-07-01

    A case is reported of aortocaval fistula (ACF) as an infrequent complication of an aneurysm of the abdominal aorta (AAA) that debuted clinically with pain in the right lumbar fossa and kidney failure. the diagnosis was made by helicoid computed tomography (HCT) and confirmed surgery. HCT findings consisted of an early accentuation of the inferior vena cava (ICV) in the arterial phase, and visualization of the communication between the aorta and inferior vena cava. (Author) 8 refs.

  19. Comparative study of the characteristics of some suction devices for gas sampling applications

    International Nuclear Information System (INIS)

    Donguy, R.; Drouet, J.

    1959-06-01

    Gas sampling (used to determine the characteristics of dusts or aerosols contained in a gas) needs a suction device. In order to select the right device and the right conditions of use, the characteristics and performances of various suction devices (helicoidal and centrifugal aspirators, air pumps, volumetric pumps) have been experimentally measured: flow rate, head loss, sampling volume and duration, aerosol and dust concentration, gas density, nature of the gas, suction circuit configuration, etc

  20. The motion of a classical particle with spin

    International Nuclear Information System (INIS)

    Amorim, R.

    1983-01-01

    A set equations of motion for a classical charged point particle with magnetic moment is proposed. These equations are obtained from a self-consistent variational principle and avoid the unphysical helicoidal motions characteristic of the theories that satisfy the condition S sup(μν) u sub(ν) = 0. The theories that satisfy the condiction S sup(μν) p sub(ν) = 0 are unified with the present theory in a trivial way. (Author) [pt

  1. Preliminary study of the thermo-hydraulic behaviour of the binary breeder reactor

    International Nuclear Information System (INIS)

    Silveira Luz, M. da; Ferreira, W.J.

    1984-06-01

    Continuing the development of the Binary Breeder Reactor, its physical configuration and the advantages of differents types of spacers are analysed. In order to simulate the thermo-hydraulic behaviour and obtain data for a preliminary evaluation of the core geometry, the COBRA III C code was used to study the effects of the lenght and diameter of the fuel element, the coolant inlet temperature, the system pressure, helicoidal pitch and the pitch to diameter ratio. (Author) [pt

  2. Process of distilling, heating, and condensing bituminous shales, etc

    Energy Technology Data Exchange (ETDEWEB)

    Bayle, M

    1892-04-26

    The distillation apparatus is composed of a vertical cylinder, whose walls are formed of metal, cast iron, sheet iron, cast or welded steel, refractory clay or other convenient material. The cylinder is fixed. Along its axis passes a shaft, receiving a rotary motion from an endless screw, engaging with a helicoidal toothed wheel. The shaft carries a series of plates, moving with it, over which circulates successively the mineral, pushed from one plate to a lower one by a small scraper.

  3. Flow modelling of a newtonian fluid by two regions- the region of pure fluid and porous region

    International Nuclear Information System (INIS)

    Sampaio, R.; Gama, R.M.S. da

    1983-01-01

    A model of flow with two regions is presented using mixture theory. One region contains only pure fluid and the other a mixture of fluid and porous rigid solid. Compatibility conditons on the pure fluid-mixture interface are carefully discussed. The theory is used to solve a problem of a flow induced by pressure gradient and helicoidal motion of an impermeable cylinder on two rings one of pure fluid and another of mixture. (Author) [pt

  4. Comparative study of the characteristics of some suction devices for gas sampling applications; Etude comparative des caracteristiques de quelques dispositifs d'aspiration a l'usage des prelevements de gaz

    Energy Technology Data Exchange (ETDEWEB)

    Donguy, R.; Drouet, J.

    1959-06-15

    Gas sampling (used to determine the characteristics of dusts or aerosols contained in a gas) needs a suction device. In order to select the right device and the right conditions of use, the characteristics and performances of various suction devices (helicoidal and centrifugal aspirators, air pumps, volumetric pumps) have been experimentally measured: flow rate, head loss, sampling volume and duration, aerosol and dust concentration, gas density, nature of the gas, suction circuit configuration, etc.

  5. Refined Betz limit for rotors with a finite number of blades

    DEFF Research Database (Denmark)

    Okulov, Valery; Sørensen, Jens Nørkær

    2008-01-01

    The criterion of Betz for optimum rotors with a finite number of blades is revisited and used to determine the performance of wind turbines. The Betz criterion states that ideal efficiency is obtained when the distribution of circulation along the blade produces a rigidly helicoid wake that moves...... model is consistent with the general momentum theory and enables for the first time to determine the theoretical maximum efficiency of rotors with an arbitrary number of blades....

  6. Interaction of a high-order Bessel beam with a submerged spherical ultrasound contrast agent shell - Scattering theory.

    Science.gov (United States)

    Mitri, F G

    2010-03-01

    Acoustic scattering properties of ultrasound contrast agents are useful in extending existing or developing new techniques for biomedical imaging applications. A useful first step in this direction is to investigate the acoustic scattering of a new class of acoustic beams, known as helicoidal high-order Bessel beams, to improve the understanding of their scattering characteristics by an ultrasound contrast agent, which at present is very limited. The transverse acoustic scattering of a commercially available albuminoidal ultrasound contrast agent shell filled with air or a denser gas such as perfluoropropane and placed in a helicoidal Bessel beam of any order is examined numerically. The shell is assumed to possess an outer radius a=3.5 microns and a thickness of approximately 105 nm. Moduli of the total and resonance transverse acoustic scattering form functions are numerically evaluated in the bandwidth 0scattering of a helicoidal Bessel beam of order m1 so that the dynamics of contrast agents would be significantly altered. The main finding of the present theory is the suppression or enhancement for a particular resonance that may be used to advantage in imaging with ultrasound contrast agents for clinical applications. 2009 Elsevier B.V. All rights reserved.

  7. Implementação de um sistema de localização espacial de regiões cerebrais em tempo real para aplicação de TMS por co-registro com fMRI

    OpenAIRE

    André Salles Cunha Peres

    2008-01-01

    Nos últimos 20 anos tivemos um grande avanço na neurociência e nas técnicas de avaliação do sistema nervoso em humanos em uma tentativa inicial de compreensão de seu funcionamento. Colaboram com esse avanço técnicas como a eletroencefalografia (EEG), tomografia com-putadorizada (CT), tomografia por emissão de pósitron (PET), ressonância magnética funcional (fMRI), que geram mapas estatísticos de atividade cerebral, e a estimulação magnética transcrania-na (TMS), que se utiliza de pulsos de...

  8. Solitary pulmonary nodule: radiologic features and diagnostic approach; Nodulo pulmonar solitario: caracteristicas radiologicas y abordaje diagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Cambronero, Luis Enrique

    2012-07-01

    A literature review is conducted on the solitary pulmonary nodule, to determine the diagnostic methods and specific characteristics. The diagnostic methods used have been: chest radiography, computed tomography, positron emission tomography and magnetic resonance imaging. The radiological features are defined: location, size, definition of contours or edges (margins), densitometric and attenuation characteristics, cavitation, air bronchogram, growth, doubling time, satellite nodules, nutrient vessels [Spanish] Una revision bibliografica es realizada sobre el nodulo pulmonar solitario, para determinar los metodos de diagnostico y caracteristicas especificas. Los metodos de diagnostico utilizados han sido: la radiografia de torax, tomografia computarizada, tomografia por emision de positrones y resonancia magnetica. Las caracteristicas radiologicas son definidas: localizacion, tamano, definicion de los bordes o contornos (margenes), caracteristicas densitometricas y de atenuacion, cavitacion, broncograma aereo, crecimiento, tiempo de duplicacion, nodulos satelite, vasos nutrientes.

  9. Síndrome de Kartagener: relato de caso

    Directory of Open Access Journals (Sweden)

    Swensson Rubem C.

    2003-01-01

    Full Text Available A Síndrome de Kartagener é causada por uma doença autossômica recessiva rara, que apresenta uma tríade composta por pansinusite crônica, bronquiectasia e situs inversus com dextrocardia. A incidência desta desordem genética é estimada em 1/25.000. Nosso objetivo é, neste trabalho, aduzir dados novos àqueles que pesquisam o assunto, para que estejam atentos, acompanhando os pacientes e esperando o aparecimento eventual desta malformação. Foram realizadas tomografias computadorizadas do tórax, abdome e crânio, além da tomografia computadorizada de alta resolução do tórax, audiometria, imitanciometria e vídeo-naso-fibroscopia.

  10. Visualização do manto cerebral após tratamento de hidrocéfalo congênito: relato de um caso

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Cavalcanti

    1986-06-01

    Full Text Available O propósito deste registro é relatar o caso de recém-nascido com hidrocefalia que, após derivação ventrículo-peritoneal passou a apresentar evolução próxima ao normal do ponto de vista neurológico, bem como visualização à tomografia computadorizada do manto cerebral não observado em exame feito anteriormente.

  11. Analysis of the results of CAT of thorax with bronchiectasis protocol, period 2000-2001 Hospital Calderon Guardia; Analisis de los resultados de TAC de torax con protocolo de bonquiectasias, periodo 2000-2001 Hospital Calderon Guardia

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco Segura, Maureen [Costa Rica

    2003-07-01

    This investigation analyses the computerized axial tomography (CAT) of thorax with protocol of bronchiectasis. It was carried out in the Servicio de Radiologia e Imagenes Medicas of the Hospital Calderon Guardia, Costa Rica. The bronchiectasis is the abnormal permanent expansion of the bronchial tuber and is important to diagnose it because the patient can suffer of pulmonary infections, these can be accompanied by bronchial blood flow and hemoptysis. When they are disseminated can be associated with significant obstruction of the aerial tract. When they are gotten into focus can be confused with neoplasia and other diseases. From the bronchiectasis diagnosis it is used methods of image such as x-ray of thorax, bronchography and computerized axial tomography (CAT) of thorax, usually the diagnosis is confirmed by means of a computerized axial tomography (CAT); which is the image of election to establish the presence and extension of the bronchiectasis. In addition, this study analyzes the radiological clinical relation in the patients which were performed the computerized axial tomography (CAT) of thorax with protocol of bronchiectasis and it identifies the most suitable radiological technique to obtain a satisfactory result in the computerized axial tomography with protocol of bronchiectasis. [Spanish] En esta investigacion se analiza la tomografia axial computarizada (TAC) de torax con protocolo de bronquiectasis realizada en el Servicio de Radiologia e Imagenes Medicas del Hospital Calderon Guardia, Costa Rica. Las bronquiectasias se definen como la dilatacion permanente anormal de los bronquios y es importante diagnosticarlas porque el paciente puede sufrir de infecciones pulmonares. Ademas, estas pueden acompanarse de flujo sanguineo bronquial y hemoptisis. Cuando estan diseminadas se pueden asociar con obstruccion significativa de la via aerea. Si estan focalizadas se pueden confundir con neoplasias u otras enfermedades. Para el diagnostico de bronquiectasias

  12. Detection of myocardial viability by means of Single Proton Emission Computed Tomography (Perfused SPECT) dual {sup 201} Tl (rest of 15 minutes, 24 late hours and 24 hours reinjection) and gated-SPECT {sup 99m} Tc-SESTAMIBI in effort or stimulation of the coronary reserves; Deteccion de viabilidad miocardica mediante tomografia por emision de foton unico (SPECT perfusorio) dual {sup 201} Talio (Reposo de 15 minutos, 24 horas tardio y 24 horas reinyeccion) y gated-SPECT {sup 99m} Tc-SESTAMIBI en esfuerzo o estimulo de reserva coronaria

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza V, R

    2004-07-01

    The objective of this work was to determine if the images of SPECT {sup 201} TI in rest of 15 minutes, 24 late hours and Gated-SPECT {sup 99m} Tc-SESTAMIBI in effort or stimulation of coronary reservation correlate with the study of 24 hours post reinjection of {sup 201}TI to determine the presence of having knitted viable myocardium. Material and methods: 29 patients were studied with coronary arterial illness (EAC) to who are carried out SPECT {sup 201} TI in rest with images of 15 minutes, 24 late hours and 24 hours reinjection, by means of the administration of {sup 201}TI to dose of 130 MBq and reinjection with 37 MBq. and Gated-SPECT {sup 99m}Tc-SESTAMIBI in effort or stimulation of coronary reservation, later to the administration of 1110 MBq. Results: 29 patients were included according to inclusion approaches and exclusion, of those which 22 (75.86%) they correspond at the masculine sex and 7 (24.13%) to the feminine one, with an average of 62.1 year-old age, 2320 segments myocardial were analysed so much it is phase post-effort as rest; they were diagnosed a total of 264 segments with heart attack, of which viability myocardium was observed in 174 segments. The statistical tests are analysis of frequencies. The non parametric test of Wilcoxon and Mann-Whitney. Conclusions: the viability myocardial at the 24 late hours and 24 hours reinjection was similar; significant difference exists between the study of 15 minutes and 24 hours reinjection, ischemic illness was also demonstrated in territories different to the heart attack area in the studies of 15 minutes, late 24 hours and 24 hours reinjection. (Author)

  13. Analysis of kinematic movement characteristics of the common center of athlete's body mass while performing the crouch start

    Directory of Open Access Journals (Sweden)

    Liudmyla Shesterova

    2017-04-01

    Full Text Available Purpose: to determine the basic conditions for minimizing the cost of effort to accelerate the movement speed of the common center of athlete's body mass in the specified direction of his movement. Material & Methods: the study used video footage for short distances of the world's leading sprinters and athletes of various qualifications. To solve the problems, we used: a method for estimating the angles between biosigns and storyboard video, method of analogies, method of the theory of similarity and dimension, the method of computer modeling, statistical analysis, estimation of physical stress and strength impulse using the method of estimating the interdependence of the developed effort on the angle of expansion between the corresponding biokinematic links. Results: it sets the basic position kinematics movement common center of the athlete's body mass (CCM, which improves the efficiency of performance crouch start. The results of the dynamics of the movement of a common force vector are presented, which determines the direction of movement of the body's CCM in three-dimensional space, ensuring its movement along the center line of the run are presented. On the basis of the observed dynamics of the change in the direction of the resultant force vector, when a crouch start is performed, it is established that the trajectory of its movement is a helicoid. Conclusion: movement of the common center of body mass is carried out along the helicoid with subsequent reduction of its radius. Changes in the length of the helix forming the radius are systematic and reflect the energy efficiency of the running costs. The dynamics of the helicoidal movement of the generating vector is observed in each supporting phase of the running step, which makes it possible to assess the stability of the dynamic stereotype manifestation of the running step, and to judge by these indicators about the degree of athlete fatigue at the distance.

  14. Geometric triangular chiral hexagon crystal-like complexes organization in pathological tissues biological collision order.

    Directory of Open Access Journals (Sweden)

    Jairo A Díaz

    Full Text Available The present study describes and documents self-assembly of geometric triangular chiral hexagon crystal like complex organizations (GTCHC in human pathological tissues. The authors have found this architectural geometric expression at macroscopic and microscopic levels mainly in cancer processes. This study is based essentially on macroscopic and histopathologic analyses of 3000 surgical specimens: 2600 inflammatory lesions and 400 malignant tumours. Geometric complexes identified photographically at macroscopic level were located in the gross surgical specimen, and these areas were carefully dissected. Samples were taken to carry out histologic analysis. Based on the hypothesis of a collision genesis mechanism and because it is difficult to carry out an appropriate methodological observation in biological systems, the authors designed a model base on other dynamic systems to obtain indirect information in which a strong white flash wave light discharge, generated by an electronic device, hits over the lines of electrical conductance structured in helicoidal pattern. In their experimental model, the authors were able to reproduce and to predict polarity, chirality, helicoid geometry, triangular and hexagonal clusters through electromagnetic sequential collisions. They determined that similar events among constituents of extracelular matrix which drive and produce piezoelectric activity are responsible for the genesis of GTCHC complexes in pathological tissues. This research suggests that molecular crystals represented by triangular chiral hexagons derived from a collision-attraction event against collagen type I fibrils emerge at microscopic and macroscopic scales presenting a lateral assembly of each side of hypertrophy helicoid fibers, that represent energy flow in cooperative hierarchically chiral electromagnetic interaction in pathological tissues and arises as a geometry of the equilibrium in perturbed biological systems. Further

  15. Geometric triangular chiral hexagon crystal-like complexes organization in pathological tissues biological collision order.

    Science.gov (United States)

    Díaz, Jairo A; Jaramillo, Natalia A; Murillo, Mauricio F

    2007-12-12

    The present study describes and documents self-assembly of geometric triangular chiral hexagon crystal like complex organizations (GTCHC) in human pathological tissues. The authors have found this architectural geometric expression at macroscopic and microscopic levels mainly in cancer processes. This study is based essentially on macroscopic and histopathologic analyses of 3000 surgical specimens: 2600 inflammatory lesions and 400 malignant tumours. Geometric complexes identified photographically at macroscopic level were located in the gross surgical specimen, and these areas were carefully dissected. Samples were taken to carry out histologic analysis. Based on the hypothesis of a collision genesis mechanism and because it is difficult to carry out an appropriate methodological observation in biological systems, the authors designed a model base on other dynamic systems to obtain indirect information in which a strong white flash wave light discharge, generated by an electronic device, hits over the lines of electrical conductance structured in helicoidal pattern. In their experimental model, the authors were able to reproduce and to predict polarity, chirality, helicoid geometry, triangular and hexagonal clusters through electromagnetic sequential collisions. They determined that similar events among constituents of extracelular matrix which drive and produce piezoelectric activity are responsible for the genesis of GTCHC complexes in pathological tissues. This research suggests that molecular crystals represented by triangular chiral hexagons derived from a collision-attraction event against collagen type I fibrils emerge at microscopic and macroscopic scales presenting a lateral assembly of each side of hypertrophy helicoid fibers, that represent energy flow in cooperative hierarchically chiral electromagnetic interaction in pathological tissues and arises as a geometry of the equilibrium in perturbed biological systems. Further interdisciplinary studies must

  16. Multipole expansion of acoustical Bessel beams with arbitrary order and location.

    Science.gov (United States)

    Gong, Zhixiong; Marston, Philip L; Li, Wei; Chai, Yingbin

    2017-06-01

    An exact solution of expansion coefficients for a T-matrix method interacting with acoustic scattering of arbitrary order Bessel beams from an obstacle of arbitrary location is derived analytically. Because of the failure of the addition theorem for spherical harmonics for expansion coefficients of helicoidal Bessel beams, an addition theorem for cylindrical Bessel functions is introduced. Meanwhile, an analytical expression for the integral of products including Bessel and associated Legendre functions is applied to eliminate the integration over the polar angle. Note that this multipole expansion may also benefit other scattering methods and expansions of incident waves, for instance, partial-wave series solutions.

  17. Cálculos termodinamicos-estructurales en proteínas: predicción de afinidades de union y diseño molecular de ligandos peptídicos

    OpenAIRE

    Luque Fernández, Irene

    2013-01-01

    Esta tesis se centra en la aplicación de metodologías de cálculo de magnitudes termodinámicas a partir de consideraciones estructurales al desarrollo de estrategias racionales de diseño molecular de ligandos peptídicos. Con objeto de comprobar que la metodología de cálculo es suficientemente sensible para ello se ha aplicado previamente al desarrollo de una escala termodinámico-estructural de propensión helicoidal que se encuentra en excelente concordancia con otras escalas existentes en la l...

  18. HL-LHC tracking challenge

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    We organize on the Kaggle platform a data science competition to stimulate both the ML and HEP communities to renew core tracking algorithms in preparation of the next generation of particle detectors at the LHC. In a nutshell : one event has 100.000 3D points ; how to associate the points onto 10.000 unknown approximately helicoidal trajectories ? avoiding combinatorial explosion ? you have a few seconds. But we do give you 100.000 events to train on. We ran ttbar+200 minimum bias event into ACTS a simplified (yet accurate) simulation of a generic LHC silicon detectors, and wrote out the reconstructed hits, with matching truth. ...

  19. In-service inspection of nuclear power plants

    International Nuclear Information System (INIS)

    Asty, M.; Saglio, R.

    1984-10-01

    The French Commissariat a l'Energie Atomique (Atomic Energy Commission) developed two new non destructive control techniques, focused ultrasonics and multi-frequency eddy currents, which have been shown to allow a better detection and characterization of defects. We present here some of the in-service inspection devices which have been designed for field application of these techniques on the PWR reactors built by EDF, inspection devices of the PWR steam generator tubing and the now developing specific device for main tank and helicoidal tubing steam generator of Super-Phenix 1 [fr

  20. Valoración de los resultados del tratamiento quirúrgico del pie plano estático

    OpenAIRE

    Paz Jiménez, José; Amigo Fernandez, A.; Romo Contreras, I.

    1989-01-01

    La deformidad fundamental del pie plano es el valgo de talón. Existe siempre un movimiento helicoidal en pronación del retropic y supinación del antepic. En este trabajo se hace una revisión de los pacientes tratados en nuestro Servicio a lo largo de diez años, que han sido sometidos a intervención quirúrgica, mayoritariamente artrodesis. - El fotopodograma constituye un excelente método para controlar la evolución de un pie plano. El pie plano por astrágalo vertical es irreductible des...

  1. No rotating U.S. Testing of thin walled tubes

    International Nuclear Information System (INIS)

    Furlan, J.; Boulanger, G.; Mogavero, R.

    1981-07-01

    Thin walled tube ultrasonic testing is performed, with Lamb waves, using annular transducers and conical or helicoidal mirrors. The main advantage of this already known system is dispensing with rotation of tube and/or transducer. High speed control (30 cm/s and more) is then allowed. The present paper describes the parameters influencing the sensitivity has been improved by searching, theoretically and practically, the best suited Lamb wave modes, and by using transducers which are well characterized. Practical example of cladding tube U.S. testing is described

  2. Direct calculation of wind turbine tip loss

    DEFF Research Database (Denmark)

    Wood, D.H.; Okulov, Valery; Bhattacharjee, D.

    2016-01-01

    . We develop three methods for the direct calculation of the tip loss. The first is the computationally expensive calculation of the velocities induced by the helicoidal wake which requires the evaluation of infinite sums of products of Bessel functions. The second uses the asymptotic evaluation......The usual method to account for a finite number of blades in blade element calculations of wind turbine performance is through a tip loss factor. Most analyses use the tip loss approximation due to Prandtl which is easily and cheaply calculated but is known to be inaccurate at low tip speed ratio...

  3. The motion of a classical spinning point particle in a Riemann-Cartan space-time

    International Nuclear Information System (INIS)

    Amorim, R.

    1983-01-01

    A consistent set of equations of motion for classical charged point particles with spin and magnetic dipole moment in a Riemann-Cartan space-time is generated from a generalized Lagrangean formalism. The equations avoid the spurius free helicoidal solutions and at the same time conserve the canonical condition of normalization of the 4-velocity. The 4-velocity and the mechanical moment are paralell in this theory, where the condition of orthogonality between the spin and the 4-velocity is treated as a non-holonomic one. (Author) [pt

  4. The theory and practice of worm gear drives

    CERN Document Server

    Dudás, Ilés

    2005-01-01

    Worm gears are special gears that resemble screws, and can be used to drive other gears. Worm gears, enable two non-touching shafts in a machine to mesh (join) together. This publication, unique in that it combines both theoretical and practical design aspects, including the latest results of research and development, provides detailed treatment of the theory and production of worm drives, as well as the overarching subject of production geometry of helicoidal surfaces.Included are mathematical models for a number of practical applications; a description of dressing equipment r

  5. Analysis of the sweeped actuator line method

    OpenAIRE

    Nathan Jörn; Masson Christian; Dufresne Louis; Churchfield Matthew

    2015-01-01

    The actuator line method made it possible to describe the near wake of a wind turbine more accurately than with the actuator disk method. Whereas the actuator line generates the helicoidal vortex system shed from the tip blades, the actuator disk method sheds a vortex sheet from the edge of the rotor plane. But with the actuator line come also temporal and spatial constraints, such as the need for a much smaller time step than with actuator disk. While the latter one only has to obey the Cour...

  6. Surgical repair of a pseudoaneurysm of the ascending aorta after aortic valve replacement

    Directory of Open Access Journals (Sweden)

    Almeida Rui Manuel Sequeira de

    2001-01-01

    Full Text Available We report the case of a patient with a pseudoaneurysm of the ascending aortic clinically diagnosed 5 months after surgical replacement of the aortic valve. Diagnosis was confirmed with the aid of two-dimensional echocardiography and helicoidal angiotomography. The corrective surgery, which consisted of a reinforced suture of the communication with the ascending aorta after opening and aspiration of the cavity of the pseudoaneurysm, was successfully performed through a complete sternotomy using extracorporeal circulation, femorofemoral cannulation, and moderate hypothermia, with no aortic clamping.

  7. EDF research on fast neutron reactors

    International Nuclear Information System (INIS)

    In order to make possible the calculation of the temperatures of the sodium, of the sheath and of the fuel in fast reactor assemblies, taking into account the mixing phenomena induced by the helicoidal wires, two design codes have been developed. Those codes have then been adapted for their integration in the Superalcyon system. This system shall constitute the reference tool for the development of those codes that shall manage Phenix, and other reactors of the family. Cooling accidents, thermohydraulic studies, and steam generator studies are also in progress

  8. TrackML : The High Energy Physics Tracking Challenge

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    We organize on the Kaggle platform a  data science competition to stimulate both the ML and HEP communities to renew core tracking algorithms in preparation of the next generation of particle detectors at the LHC.    In a nutshell : one event has 100.000 3D points  ; how to associate the points onto 10.000 unknown approximately helicoidal trajectories ? avoiding combinatorial explosion ? you have a few seconds. But we do give you 100.000 events to train on. We ran ttbar+200 minimum bias event into ACTS a simplified (yet accurate) simulation of a generic LHC silicon detectors, and wrote out ...

  9. Análisis mecánico por elementos finitos de una antena UHF en la órbita de Marte

    OpenAIRE

    Moreno García, Carlos

    2015-01-01

    El proyecto desarrolla el diseño mecánico de una antena helicoidal en banda UHF que será parte de un satélite cuyo destino final será Marte. Los principales objetivos de la misión son: Buscar trazas o evidencia de metano y otros gases atmosféricos que podrían manifestar signos de procesos biológicos o geológicos activos, es decir, buscar indicios de vida pasada en Marte Poner a prueba la tecnología necesaria para posteriores misiones europeas a Marte. El proyecto se centrará en la...

  10. Cementation unit for radioactive wastes

    International Nuclear Information System (INIS)

    Dellamano, Jose Claudio; Vicente, Roberto; Lima, Jose Rodrigues de

    2001-01-01

    This communication describes the waste cementation process and facility developed at Instituto de Pesquisas Energeticas e Nucleares - IPEN. The process is based on 200 litres batch operation, in drum mixing, with continuous cement feeding. The equipment is a single recoverable helicoidal mixer and a turning table that allows the drum to rotate during the mixing operation, simulating a planetary mixer. The facility was designed to treat contact handled liquids and wet solid wastes, but can be adapted for shielded equipment and remote operation. (author)

  11. Process of treating carbonaceous substances

    Energy Technology Data Exchange (ETDEWEB)

    1938-12-16

    A process is described of removing halogens or halogen compounds (or both) from the products which form when carbonaceous substances are treated thermally in the presence of halogens or halogen compounds, consisting of passing the reaction products at the same temperature with a substance able to fix halogens or acid halides through an apparatus included between the receiver and the heat exchanger, which contains, in a relatively restricted space, internal elements obliquely disposed in relation to the direction of the flow, stretched in this direction and constituted preferably of helicoidal passages.

  12. Resonant fields created by spiral electric currents in Tokamaks

    International Nuclear Information System (INIS)

    Fernandes, A.S.; Caldas, I.L.

    1985-01-01

    The influence of the resonant magnetic perturbations, created by electric currents in spirals, on the plasma confinement in a tokamak with circular section and large aspect ratio is investigated. These perturbations create magnetic islands around the rational magnetic surface which has the helicity of the helicoidal currents. The intensities of these currents are calculated in order to the magnetic islands reach the limiter or others rational surfaces, what could provoke the plasma disrupture. The electric current intensities are estimated, in two spiral sets with different helicities, which create a predominantly stocastic region among the rational magnetic surfaces with these helicities. (L.C.) [pt

  13. ANALISIS COSTE-EFECTIVIDAD DE DISTINTOS MÉTODOS DE DIAGNÓSTICO POR IMAGEN DEL TROMBOEMBOLISMO PULMONAR AGUDO

    Directory of Open Access Journals (Sweden)

    Stella Maris Batallés

    2009-01-01

    Full Text Available La técnica diagnóstica óptima para detectar tromboembolismo pulmonar agudo (TEP continúa en discusión. La gammagrafía pulmonar de ventilación/perfusión ha sido el examen preferido durante décadas, pero con el advenimiento de nuevas pruebas de imágenes las posibilidades diagnósticas se ampliaron, siendo necesario evaluarlas desde la perspectiva del coste y de la efectividad. El objetivo de este trabajo fue evaluar distintos métodos de diagnóstico por imagen para detectar TEP agudo para determinar el más coste-efectivo. Métodos. Análisis de coste-efectividad (CE empleando un árbol de decisiones para modelar distintas pruebas (centellograma V/Q, TC helicoidal, angiografía por tomografía computada multidetector (TCMD, resonancia magnética por imágenes (RMI y arteriografía convencional. Se obtuvieron valores de sensibilidad, especificidad, valor predictivo positivo (VPP y negativo (VPN de las pruebas diagnósticas. Resultado medido: "caso detectado de TEP". Los costes evaluados fueron los directos, expresados en euros (t, incluyendo los secundarios a las complicaciones de los métodos diagnósticos. Se realizó un análisis de sensibilidad de una vía para evaluar la robustez de las conclusiones. Resultados. No se eliminaron pruebas por dominancia extendida. La tasa cruda de CE para TCMD fue de 486 t por cada caso de TEP detectado. El coste marginal entre la TC helicoidal y el centellograma V/Q fue de 103 t para detectar 8 casos adicionales de TEP, mientras que el coste marginal entre la TCMD y la TC helicoidal fue de 229 t para detectar un caso adicional de TEP. Conclusiones. La prueba diagnóstica más coste-efectiva fue la TCMD, hallazgo que mostró robustez en el análisis de sensibilidad. Sin embargo, el análisis de C-E incremental nos mostró que la TCMD costó 229 t más respeto a la TC helicoidal para lograr una mínima mejora en la efectividad de la prueba (detección de TEP agudo. El alto valor predictivo negativo de

  14. Aspectos radiológicos da atresia brônquica: relato de três casos e revisão da literatura Radiological aspects of bronchial atresia: report of three cases and review of the literature

    Directory of Open Access Journals (Sweden)

    Alexandre da Silva Neu

    2003-01-01

    Full Text Available A atresia brônquica é uma anomalia congênita rara que usualmente produz massa justa-hilar com hipertransparência distal à radiografia simples. A maioria dos pacientes é jovem e não apresenta sintomas. A tomografia computadorizada confirma o diagnóstico, permitindo o manejo conservador nos casos assintomáticos. Os autores relatam três casos de atresia brônquica. Um caso, de particular interesse, estava associado a volumosa broncocele em paciente do sexo feminino, de 45 anos de idade, que apresentou quadro sintomático de infecção respiratória. O diagnóstico foi estabelecido por meio dos achados da radiologia convencional, da tomografia computadorizada e da comparação com radiografias convencionais e tomografia linear prévios, que já demonstravam alterações. Realizou-se uma revisão sobre os achados clínicos e radiológicos dessa malformação.Bronchial atresia is a rare congenital abnormality that usually shows a juxta-hilar mass with distal radiolucency on conventional x-ray films. Most patients are young and have no symptoms. Computed tomography usually confirms the diagnosis, allowing conservative management of the asymptomatic cases. The authors report three cases of bronchial obstruction. One of the patients was of particular importance and interest, a 45-year-old female patient with symptoms of respiratory infection, due to the association with a bulky bronchocele. The diagnosis was made by analyzing the findings of conventional x-ray films and computed tomography, and the comparison with previous conventional x-ray films and linear tomography, which had already demonstrated abnormalities. A literature review on the clinical and radiological findings of this pulmonary malformation is presented.

  15. Avaliação da macroporosidade e da densidade de partículas do solo através da microtomografia de raios-x

    Directory of Open Access Journals (Sweden)

    A. Macedo

    1999-12-01

    Full Text Available A Ciência do Solo procura compreender e modelar os fenômenos ocorridos no solo, principalmente na zona não saturada. Como o entendimento de muitos desses fenômenos exige determinações em escalas que permitam incorporar aos modelos a variabilidade de poros e agregados, desenvolveu-se, na Embrapa Instrumentação Agropecuária, um tomógrafo de raios-X, de resolução micrométrica, com o objetivo de se obterem imagens, de forma não-destrutiva, de amostras de solo, com resolução espacial igual ou inferior a 100 μm. Foi possível projetar e construir um equipamento, de alta resolução, com baixo custo, comparativamente aos equipamentos comerciais disponíveis, cujos preços são proibitivos para aplicações em solo. Obtiveram-se imagens de amostras de solos com estrutura deformada, compostos por agregados de 212 a 250 μm, nos quais foram identificados poros medindo 100 μm ou menos. Poros dessas dimensões foram visualizados, também, em tomografias de amostras compostas de grãos de areia de 1 mm e capilares de vidro com diâmetros internos de 100, 200 e 300 μm. Tomografias de amostras não deformadas de solos evidenciaram, além de poros de 200 a 800 μm, partículas de alta densidade não-detectáveis com a tomografia de resolução milimétrica.

  16. CALCIFICAÇÃO DISTRÓFICA EM SEIO MAXILAR DE PACIENTE PEDIÁTRICO COM TRANSPLANTE HEPÁTICO E PIGMENTAÇÃO DO ÓRGÃO DENTAL

    Directory of Open Access Journals (Sweden)

    Adriana Furtado de Macedo

    2017-11-01

    Full Text Available RESUMO Objetivo: Relatar um caso de calcificação distrófica intensa no interior do seio maxilar em uma criança com transplante hepático e órgãos dentais pigmentados por hiperbilirrubinemia. Descrição do caso: Paciente do sexo feminino, 12 anos de idade, com transplante hepático efetuado aos 7 anos de vida devido à atresia de vias biliares extra-hepática, uso de tacrolimus imunossupressor (2 mg diários. No exame clínico intrabucal, observou-se a presença de pigmentação esverdeada no órgão dental por bilirrubina. Efetuou-se um exame de tomografia computadorizada volumétrica de feixe cônico para análise da densidade radiográfica dos elementos dentais pigmentados. Mediante interpretação da imagem pela escala de Hounsfield, não foi constatada nenhuma alteração na densidade radiográfica das estruturas do órgão dental. No entanto, a tomografia computadorizada evidenciou a presença de calcificação distrófica intensa em região de seio maxilar. Comentários: A alteração de imagem observada no exame de tomografia computadorizada demonstrou achado radiográfico relevante, com presença de radiopacidades no interior do seio maxilar decorrentes de sinusites fúngicas ou não fúngicas. O relato desse caso é relevante por apresentar alteração de imagem radiográfica exacerbada associada a quadros infecciosos agudos que podem comprometer o estado sistêmico do paciente imunossuprimido.

  17. Dos obras del arquitecto Azpiazu. España

    Directory of Open Access Journals (Sweden)

    Azpiazu Ordóñez, José Ramón

    1991-04-01

    Full Text Available Two recent works of the Architect J. R. Azpiazu are shown in this issue. The interest of each of them is based in punctual aspects with original constructive solutions: — At first, BUSINESS BUILDING IN SANTANDER, the project is very interesting mainly by the planning and design of the structure in wood reenforcement with laminated steel elements. — In the second, BANK OFFICE IN ORIHUELA, the interest of the constructive and formal solution in the helicoidal stair in structural concrete, without central element is the main subject.

    Se presentan en este trabajo dos obras recientes del Arquitecto José Ramón Azpiazu. El interés de cada una de ellas radica en aspectos puntuales, con soluciones constructivas de cierta originalidad: — En la primera, EDIFICIO DE OFICINAS EN SANTANDER, interesa de modo especial el planteamiento adoptado para el refuerzo de la estructura de madera existente realizado a base de elementos de acero laminado. — En la segunda, SUCURSAL DE BANCO EN ORÍ HUELA, el mayor interés radica en la solución constructiva y formal de la escalera helicoidal de hormigón armado, ejecutada sin vástago central.

  18. Blackfolds, plane waves and minimal surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Armas, Jay [Physique Théorique et Mathématique, Université Libre de Bruxelles and International Solvay Institutes, ULB-Campus Plaine CP231, B-1050 Brussels (Belgium); Albert Einstein Center for Fundamental Physics, University of Bern,Sidlerstrasse 5, 3012 Bern (Switzerland); Blau, Matthias [Albert Einstein Center for Fundamental Physics, University of Bern,Sidlerstrasse 5, 3012 Bern (Switzerland)

    2015-07-29

    Minimal surfaces in Euclidean space provide examples of possible non-compact horizon geometries and topologies in asymptotically flat space-time. On the other hand, the existence of limiting surfaces in the space-time provides a simple mechanism for making these configurations compact. Limiting surfaces appear naturally in a given space-time by making minimal surfaces rotate but they are also inherent to plane wave or de Sitter space-times in which case minimal surfaces can be static and compact. We use the blackfold approach in order to scan for possible black hole horizon geometries and topologies in asymptotically flat, plane wave and de Sitter space-times. In the process we uncover several new configurations, such as black helicoids and catenoids, some of which have an asymptotically flat counterpart. In particular, we find that the ultraspinning regime of singly-spinning Myers-Perry black holes, described in terms of the simplest minimal surface (the plane), can be obtained as a limit of a black helicoid, suggesting that these two families of black holes are connected. We also show that minimal surfaces embedded in spheres rather than Euclidean space can be used to construct static compact horizons in asymptotically de Sitter space-times.

  19. Precursor phenomena at the magnetic ordering of the cubic helimagnet FeGe

    Energy Technology Data Exchange (ETDEWEB)

    Baenitz, Michael; Schmidt, Marcus [MPI CPfS, Dresden (Germany); Wilhelm, Heribert [Diamond Light Source Ltd., Chilton (United Kingdom); Roessler, Ulrich K.; Bogdanov, Alexei N.; Leonov, Andrey A. [IFW Dresden (Germany)

    2011-07-01

    We report on detailed magnetic measurements on the cubic helimagnet FeGe in external magnetic fields parallel to the direction and temperatures in the vicinity of the onset of long-range magnetic order at T{sub c}{approx}278 K. Depending on the temperature and field, a helical state (Hhelicoids propagating in directions perpendicular to the applied field. We suggest that the observation of this A{sub 2}-phase can be explained by hexagonal arrays of spiral domains consisting essentially of helicoids.

  20. Blackfolds, plane waves and minimal surfaces

    Science.gov (United States)

    Armas, Jay; Blau, Matthias

    2015-07-01

    Minimal surfaces in Euclidean space provide examples of possible non-compact horizon geometries and topologies in asymptotically flat space-time. On the other hand, the existence of limiting surfaces in the space-time provides a simple mechanism for making these configurations compact. Limiting surfaces appear naturally in a given space-time by making minimal surfaces rotate but they are also inherent to plane wave or de Sitter space-times in which case minimal surfaces can be static and compact. We use the blackfold approach in order to scan for possible black hole horizon geometries and topologies in asymptotically flat, plane wave and de Sitter space-times. In the process we uncover several new configurations, such as black helicoids and catenoids, some of which have an asymptotically flat counterpart. In particular, we find that the ultraspinning regime of singly-spinning Myers-Perry black holes, described in terms of the simplest minimal surface (the plane), can be obtained as a limit of a black helicoid, suggesting that these two families of black holes are connected. We also show that minimal surfaces embedded in spheres rather than Euclidean space can be used to construct static compact horizons in asymptotically de Sitter space-times.

  1. Centro de cálculo IBM - Francfort (Alemania Federal

    Directory of Open Access Journals (Sweden)

    Apel, Beckert, Becker, Arquitectos

    1972-03-01

    Full Text Available This centre comprises a tall building, of approximately square cross section, and a 10 m high rectangular block. The first one houses the offices, and the second contains an IBM computer and accessories. The structure is of reinforced concrete for the vertical members, and ribbed flooring slabs for the horizontal ones. The external enclosing medium consists of precast concrete elements, and large glazed surfaces. The are features of ornamental significance, such as the indoor helicoidal stairs of unfaced concrete, and the slab covered square, with its garden and artificial lake areas. Parking space is provided in the basements.El complejo se compone de: — un rascacielos con planta sensiblemente cuadrada y 38 m de altura, y — un bloque rectangular, más bajo, de 9,90 m de alto. El primero alberga las oficinas, y el segundo se destina a cubrir todas las exigencias que se derivan del funcionamiento de un ordenador IBM. Su estructura, a base de núcleos verticales de hormigón armado, forjados nervados y cerramientos compuestos de piezas de hormigón, prefabricadas, con grandes zonas acristaladas. Hay motivos ornamentales, como la escalera helicoidal interior, de hormigón visto, y la plaza enlosada, con estanques y jardineras. Aparcamiento en el sótano.

  2. Prenatal forehead edema in 4p- deletion: the 'Greek warrior helmet' profile revisited.

    Science.gov (United States)

    Levaillant, J M; Touboul, C; Sinico, M; Vergnaud, A; Serero, S; Druart, L; Blondeau, J R; Abd Alsamad, I; Haddad, B; Gérard-Blanluet, M

    2005-12-01

    Deletion of short arm of chromosome 4 is difficult to ascertain prenatally, and can be missed. A prenatal suspicion of 4p- syndrome was thoroughly investigated by using two-dimensional and three-dimensional sonography, with a description of the fetal face dysmorphological pattern. The cytogenetic confirmation, obtained by karyotype and FISH technique, allowed a precise description of the prenatal abnormalities. Post-termination tridimensional helicoidal scanner of the fetal face was performed. The main anomaly discovered using two-dimensional sonography was the presence of a strikingly thick prefrontal edema (8 mm, twice the normal values, at 22 weeks: 3.81 +/- 0.62 mm). Three-dimensional sonography showed the classical postnatal profile, with the phenotypic aspect of a 'Greek warrior helmet'. Nasal bones were normal in size and placement, confirmed by helicoidal scanner. Prenatal diagnosis of 4p deletion syndrome can be difficult, and it is the presence of prefrontal edema, associated with more subtle facial anomalies (short philtrum, microretrognathia) which should trigger cytogenetic investigation for 4p- deletion, even with only borderline growth retardation. Copyright 2005 John Wiley & Sons, Ltd

  3. Operation and post operative examinations on the 1 MW test section SDP-1

    International Nuclear Information System (INIS)

    Casalini, P.; Valentini, P.; Urbani, A.

    1975-01-01

    The tests carried out were essentially, of general interest and could regard the general Performance and the behavior of the materials. The last aspect was rather interesting as the steam generator coil consists of a steel which has not been yet homologated in Italy. As already specified, the geometry of the steam generator was somewhat particular: it consisted of a stainless steel (Type AISI 316) cylindrical envelope with a diameter of about 500 mm and about 4 m high, with inside an helicoidal duct having a rectangular section, also in AISI 316 stainless steel. Three helicoidal tubes with an outer diameter of 26,9 mm and a thickness of 5 mm, out of ferritic steel - Type Mannesman F 11 were arranged inside the duct. The rectangular duct was run through by sodium downwards, while water/steam was running through the three parallel tubes upwards. The main characteristics pertaining to the steam generator and the nominal operational data are given. All the tests carried out on the tube coil resulted in noticeable alteration due to operation in sodium. In particular, with regard to the absence of variation of the carbon content between the inner and outer side in all the specimens analyzed, one can conclude that no considerable mass transfer occurred in the tube

  4. Creep of ex-service AISI-316H steel at very low strain rates

    Energy Technology Data Exchange (ETDEWEB)

    Kloc, Lubos; Sklenicka, Vaclav [Academy of Sciences of the Czech Republic, Brno (Czech Republic). Inst. of Physics of Materials; Spindler, Michael [British Energy Generation, Barbwood, Gloucester (United Kingdom)

    2010-07-01

    The creep response of ex-service Type 316H austenitic steel was investigated at temperatures from 470 to 550 C and stresses from 80 to 120 MPa. These conditions lead to very low strain rates. Both helicoid spring specimen tests and conventional uniaxial creep tests were used to measure these very low creep strains. An internal stress model was used to analyse the creep curves and the results were compared to creep curves obtained on a Type 316H in the as-received condition, which for austenitic steels is after solution heat treatment. The creep behavior of the ex-service steel was very similar to that of the as-received steel. Thus, no creep damage or significant change of microstructure was detected during the service period of 65,000 hours at {proportional_to} 520 C. It was found that the helicoid spring specimen technique provides results compatible with that of conventional creep tests, but with superior accuracy with very low creep strains. (orig.)

  5. Modeling Textural Processes during Self-Assembly of Plant-Based Chiral-Nematic Liquid Crystals

    Directory of Open Access Journals (Sweden)

    Yogesh K. Murugesan

    2010-12-01

    Full Text Available Biological liquid crystalline polymers are found in cellulosic, chitin, and DNA based natural materials. Chiral nematic liquid crystalline orientational order is observed frozen-in in the solid state in plant cell walls and is known as a liquid crystal analogue characterized by a helicoidal plywood architecture. The emergence of the plywood architecture by directed chiral nematic liquid crystalline self assembly has been postulated as the mechanism that leads to optimal cellulose fibril organization. In natural systems, tissue growth and development takes place in the presence of inclusions and secondary phases leaving behind characteristic defects and textures, which provide a unique testing ground for the validity of the liquid crystal self-assembly postulate. In this work, a mathematical model, based on the Landau-de Gennes theory of liquid crystals, is used to simulate defect textures arising in the domain of self assembly, due to presence of secondary phases representing plant cells, lumens and pit canals. It is shown that the obtained defect patterns observed in some plant cell walls are those expected from a truly liquid crystalline phase. The analysis reveals the nature and magnitude of the viscoelastic material parameters that lead to observed patterns in plant-based helicoids through directed self-assembly. In addition, the results provide new guidance to develop biomimetic plywoods for structural and functional applications.

  6. Aminosilanes derived from 1H-benzimidazole-2(3H)-thione

    Energy Technology Data Exchange (ETDEWEB)

    Palomo-Molina, Juliana [Facultad de Ciencias Químicas, Universidad de Colima, Carretera Coquimatlán-Colima, Coquimatlán Colima 28400 (Mexico); García-Báez, Efrén V. [Unidad Profesional Interdisciplinaria de Biotecnología, Instituto Politécnico Nacional, Avenida Acueducto s/n, Barrio La Laguna Ticomán, México DF 07340 (Mexico); Contreras, Rosalinda [Departamento de Química, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 14-740, México DF 07000 (Mexico); Barrio La Laguna Ticomán, México DF 07340 (Mexico); Pineda-Urbina, Kayim; Ramos-Organillo, Angel, E-mail: aaramos@ucol.mx [Facultad de Ciencias Químicas, Universidad de Colima, Carretera Coquimatlán-Colima, Coquimatlán Colima 28400 (Mexico)

    2015-08-12

    In two trimethylsilyl-substituted 1H-benzimidazole-2(3H)-thiones, noncovalent C—H⋯π interactions between the centroid of the benzmidazole system and the SiMe{sub 3} groups form helicoidal arrangements in one, and dimerization results in the formation of R{sub s} {sup 2}(8) rings via N—H⋯S interactions, along with parallel π–π interactions between imidazole and benzene rings, in the second compound. Two new molecular structures, namely 1,3-bis(trimethylsilyl)-1H-benzimidazole-2(3H)-thione, C{sub 13}H{sub 22}N{sub 2}SSi{sub 2}, (2), and 1-trimethylsilyl-1H-benzimidazole-2(3H)-thione, C{sub 10}H{sub 14}N{sub 2}SSi, (3), are reported. Both systems were derived from 1H-benzimidazole-2(3H)-thione. Noncovalent C—H⋯π interactions between the centroid of the benzmidazole system and the SiMe{sub 3} groups form helicoidal arrangements in (2). Dimerization of (3) results in the formation of R{sub 2}{sup 2}(8) rings via N—H⋯S interactions, along with parallel π–π interactions between imidazole and benzene rings.

  7. Aminosilanes derived from 1H-benzimidazole-2(3H)-thione

    International Nuclear Information System (INIS)

    Palomo-Molina, Juliana; García-Báez, Efrén V.; Contreras, Rosalinda; Pineda-Urbina, Kayim; Ramos-Organillo, Angel

    2015-01-01

    In two trimethylsilyl-substituted 1H-benzimidazole-2(3H)-thiones, noncovalent C—H⋯π interactions between the centroid of the benzmidazole system and the SiMe 3 groups form helicoidal arrangements in one, and dimerization results in the formation of R s 2 (8) rings via N—H⋯S interactions, along with parallel π–π interactions between imidazole and benzene rings, in the second compound. Two new molecular structures, namely 1,3-bis(trimethylsilyl)-1H-benzimidazole-2(3H)-thione, C 13 H 22 N 2 SSi 2 , (2), and 1-trimethylsilyl-1H-benzimidazole-2(3H)-thione, C 10 H 14 N 2 SSi, (3), are reported. Both systems were derived from 1H-benzimidazole-2(3H)-thione. Noncovalent C—H⋯π interactions between the centroid of the benzmidazole system and the SiMe 3 groups form helicoidal arrangements in (2). Dimerization of (3) results in the formation of R 2 2 (8) rings via N—H⋯S interactions, along with parallel π–π interactions between imidazole and benzene rings

  8. Sífilis secundária com acometimento pulmonar Secondary syphilis with pulmonary involvement

    OpenAIRE

    Ederson Valei Lopes de Oliveira; José Alves Rocha-Filho; Andreia Américo Monteiro; Eurides Maria de Oliveira Pozzeti; João Roberto Antonio

    2007-01-01

    Sífilis é doença sistêmica e infectocontagiosa causada pelo Treponema pallidum. Relata-se caso de sífilis secundária em homem de 37 anos com queixas relacionadas ao trato respiratório. Manifestações clínicas e exames de imagens, incluindo radiografia e tomografia computadorizada de tórax, sugeriram neoplasia. A avaliação dermatológica e os exames complementares (sorologia e anatomopatológico de pele) confirmaram o diagnóstico. Paciente foi tratado com aplicação semanal de penicilina G benzati...

  9. Trombose da artéria carótida interna devida a trauma penetrante no pálato mole: relato de caso

    Directory of Open Access Journals (Sweden)

    BORGES GUILHERME

    1999-01-01

    Full Text Available Descrevemos caso de trauma penetrante na região oral em criança, evoluindo com oclusão da artéria carótida interna e déficit neurológico correspondente. A tomografia computadorizada e a ressonância nuclear magnética demonstram a oclusão completa da artéria carótida interna. Enfatizamos esta rara complicação de trauma oral, comum em crianças e discutimos os aspectos patogênicos.

  10. Ombro flutuante associado à luxação escápulo-umeral posterior: relato de caso

    OpenAIRE

    Rodrigues,Alessandro Ulhôa; Veado,Marco Antonio de Castro; Melo,Gustavus Lemos Ribeiro

    2007-01-01

    Apresenta-se rara variação de ombro flutuante associada a luxação glenoumeral posterior em paciente masculino, 26 anos de idade, vítima de acidente motociclístico. Ao exame, queixava-se de dor no ombro esquerdo, limitação dos movimentos, principalmente da rotação externa. A radiografia em ântero-posterior (AP) verdadeiro mostrou fratura do colo da glenóide, sem envolvimento articular, e fratura do processo coracóide. A radiografia em perfil, axilar e a tomografia computadorizada confirmaram a...

  11. Avaliação da simetria craniana através de imagens de TC cone beam = Cranial symmetry assessment through cone-beam CT images

    OpenAIRE

    Vilella, Oswaldo de Vasconcellos; Rothier, Eduardo Kant Colunga; Vilella, Beatriz de Souza

    2014-01-01

    Objetivo: O objetivo do presente estudo foi comparar os lados direito e esquerdo de indivíduos que apresentavam simetria craniana através de 2 imagens geradas pela tomografia computadorizada cone beam (TCCB). Métodos: A amostra consistiu de 35 imagens obtidas pelo tomógrafo 3D-i-CAT (Imaging Sciences International Inc. , Hatfield, USA), sendo 13 de indivíduos do gênero masculino e 22 do gênero feminino, com idades variando de 8 a 64 anos, que apresentavam simetria facial aceitável. As imagens...

  12. Achados tomográficos das alterações abdominais pós-operatórias dos pacientes submetidos ao derivação gastrojejunal em Y-de-Roux sem anel

    Directory of Open Access Journals (Sweden)

    Fernanda Marcondes Ribas

    Full Text Available OBJETIVO: Avaliar por exame de tomografia computadorizada de pacientes submetidos à derivação gastrojejunal em Y-de-Roux, sem anel, para tratamento de obesidade mórbida. MÉTODOS: Estudaram-se 40 pacientes, encaminhados ao serviço de tomografia do Hospital Universitário Evangélico de Curitiba para avaliação diagnóstica. Encontravam-se em pós-operatório de cirurgia bariátrica tendo sido operados no mesmo hospital. Foram incluídos pacientes submetidos à operação laparoscópica com sintomas que necessitavam de avaliação tomográfica diagnóstica. Excluíram-se pacientes que tinham sido submetidos à cirurgia bariátrica por outras técnicas cirúrgicas; que tinham sido operados por outra equipe; que não concordassem com a administração de contraste iodado por via oral ou endovenosa; e que excediam o limite de peso da mesa de exame. Para análise estatística utilizou-se a média das variáveis. RESULTADOS: Os pacientes apresentaram-se com idade entre 23 a 70 anos e eram 11 homens e 29 mulheres. Não houve alterações extra-abdominais detectáveis pela tomografia de abdômen total; dos 40 pacientes avaliados, 30 apresentavam achados tomográficos dentro do limite da normalidade. A presença de estenose na anastomose gastrojejunal foi encontrada em um paciente; hérnia interna ocorreu em cinco; fístula anastomótica em um e abcesso em três dos pacientes estudados. CONCLUSÃO: A tomografia de abdome total não conseguiu informar a causa dos sintomas dos pacientes operados em 87,5% dos pacientes que procuraram re-avaliação médica por sintomas pós-operatórios da cirurgia bariátrica.

  13. Integração modular em visualizadores médicos e aposição da marcação CE do Dispositivo Médico

    OpenAIRE

    Alves, Martinha Armada Rodrigues

    2013-01-01

    Neste documento ´e feita a descrição detalhada da integração modular de um script no software OsiriX. O objectivo deste script ´e determinar o diâmetro central da artéria aorta a partir de uma Tomografia Computorizada. Para tal são abordados conceitos relacionados com a temática do processamento de imagem digital, tecnologias associadas, e.g., a norma DICOM e desenvolvimento de software. Como estudo preliminar, são analisados diversos visualizadores de imagens médica, utilizados para inves...

  14. Usando a antimatéria na medicina moderna

    OpenAIRE

    Machado,A.C.B.; Pleitez,V.; Tijero,M.C.

    2006-01-01

    Neste artigo, fazemos uma breve exposição de como um dos conceitos fundamentais da física moderna, a existência de antimatéria, tem aplicação na medicina, na chamada tomografia por emissão de pósitrons (PET na sigla em inglês). Ela consiste na produção de imagens tomográficas digitais do organismo que são obtidas pela detecção da radiação produzida na aniquilação do pósitron com o elétron.

  15. Ruptura traumática de via aérea em criança: um desafio diagnóstico

    OpenAIRE

    Ventura,Andréa Maria Cordeiro; Góes,Patrícia Freitas; Otoch,José Pinhata; Fernandes,José Carlos

    2005-01-01

    OBJETIVO: Relatar um caso de ruptura da via aérea em criança vítima de trauma torácico decorrente de queda do tanque de lavar roupas. DESCRIÇÃO: Relato de caso descritivo. O paciente pré-escolar de 34 meses, do sexo masculino foi atendido na unidade de terapia intensiva pediátrica de Hospital Universitário. Foram realizados os seguintes procedimentos: radiografia simples e tomografia de tórax, endoscopia respiratória, toracotomia, antibioticoterapia, ventilação mecânica. A radiografia simples...

  16. Complicações respiratórias em pacientes com paralisia cerebral submetidos à anestesia geral

    OpenAIRE

    Mello, Sérgio Silva de; Marques, Ronaldo Soares; Saraiva, Renato Ângelo

    2007-01-01

    JUSTIFICATIVA E OBJETIVOS: Anestesia em pacientes com paralisia cerebral (PC) pode representar um desafio para o anestesiologista. Este estudo prospectivo teve como objetivo determinar a prevalência e o risco de complicações respiratórias em crianças com PC submetidas à anestesia geral inalatória (AGI) para tomografia computadorizada (TC). MÉTODO: Participaram do estudo pacientes com idades entre 1 e 17 anos, estado físico ASA I a III, submetidos a AGI com sevoflurano e máscara laríngea para ...

  17. Oclusão bilateral das artérias carótidas internas, sífilis meningovascular e SIDA: relato de caso

    OpenAIRE

    LAMBRECHT,FLORISBERTO; SÁ,DANIEL S. DE; KOERBEL,ANDREI; TAMANINI,ALEXANDRO; MACHARETH,SÁVIO L.; SCOLA,ROSANA HERMINIA; TEIVE,HÉLIO A. G.; WERNECK,LINEU CESAR

    1999-01-01

    Relatamos um caso de obstrução bilateral na origem das artérias carótidas internas, apresentando como sinais/sintomas associados hemiparesia e hipoestesia superficial e profunda à direita, associada a sífilis meningovascular em paciente com SIDA. Tomografia de crânio apresentou pequenas lesões hipodensas, com predomínio à esquerda, e arteriografia evidenciou oclusão bilateral das artérias carótidas. A associação entre lues e SIDA não é infrequente, porém o quadro oligossintomático do paciente...

  18. Internal carotid bilateral occlusion, meningovascular syphilis and AIDS: case report

    OpenAIRE

    LAMBRECHT, FLORISBERTO; SÁ, DANIEL S. DE; KOERBEL, ANDREI; TAMANINI, ALEXANDRO; MACHARETH, SÁVIO L.; SCOLA, ROSANA HERMINIA; TEIVE, HÉLIO A. G.; WERNECK, LINEU CESAR

    1999-01-01

    Relatamos um caso de obstrução bilateral na origem das artérias carótidas internas, apresentando como sinais/sintomas associados hemiparesia e hipoestesia superficial e profunda à direita, associada a sífilis meningovascular em paciente com SIDA. Tomografia de crânio apresentou pequenas lesões hipodensas, com predomínio à esquerda, e arteriografia evidenciou oclusão bilateral das artérias carótidas. A associação entre lues e SIDA não é infrequente, porém o quadro oligossintomático do paciente...

  19. Alteraciones neuropsicológicas en el alcoholismo crónico

    OpenAIRE

    Junqué i Plaja, Carme, 1955-; Jurado, Ma. Ángeles (María Ángeles)

    1991-01-01

    El déficit neuropsicológico asociado al alcholismo abarca diversas funciones: memoria, razonamiento abstracto, solución de problemas y ha- bilidades perceptivo-motoras. Estructuralmente, los cambios cerebrales ob- servados con m i s frecuencia en la Tomografia Computarizada (TC) son la atrofia cerebral difusa y la dilatación ventricular. La dilatación ventri- cular es la medida de atrofia cerebral que m i s correlaciona con el déficit neuropsicológico. Desde ei punto de vista funcional, el fl...

  20. Hepatocarcinoma fibrolamelar: relato de um caso

    Directory of Open Access Journals (Sweden)

    Martins Rogéria de Castro

    2001-01-01

    Full Text Available O hepatocarcinoma fibrolamelar é neoplasia hepatocelular rara, diagnosticada por tomografia computadorizada e confirmada pelo exame anatomopatológico. O caso relatado foi atendido no Hospital Mater Dei de Belo Horizonte, MG. Os aspectos clínicos, radiológicos e patológicos discutidos reforçam a importância das imagens radiológicas na detecção e caracterização das neoplasias focais hepáticas.

  1. Cistos sinoviais lombares Synovial cysts of the lumbar spine

    Directory of Open Access Journals (Sweden)

    Ana Cláudia Ferreira Rosa

    2002-10-01

    Full Text Available Os cistos sinoviais localizados na coluna lombar são raros, em geral associados a alterações degenerativas das articulações facetárias, mais freqüentemente vistos na transição L4-L5. Raramente causam sintomas, que, quando ocorrem, são sobretudo lombociatalgia. O diagnóstico é feito de maneira satisfatória pela tomografia computadorizada e pela ressonância magnética e é importante para que se institua o correto tratamento dos cistos. Existem diversas formas de tratamento, desde repouso e imobilização até a injeção de corticóide no cisto sinovial guiada por tomografia computadorizada, e mesmo cirurgia nos casos refratários aos outros tipos de tratamento.Intraspinal synovial cysts of the lumbar spine are rare and commonly associated with osteoarthritis of the facet joints, particularly at level L4-L5. Symptoms are uncommon and may include low-back pain or sciatica. These cysts are accurately diagnosed by using computed tomography and magnetic resonance imaging. Diagnosis is essential for the correct management of the cysts. Several treatment options are available including rest and immobilization, computed tomography guided corticosteroids injection, and surgery in patients that are nonresponsive to other treatment methods.

  2. Transient spectral domain optical coherence tomography findings in classic MEWDS: a case report

    Directory of Open Access Journals (Sweden)

    Luciana Castro Lavigne

    2014-06-01

    Full Text Available O propósito deste estudo é descrever o caso de um paciente com síndrome dos múltiplos pontos brancos evanescentes (MEWDS, apresentando achados retinianos clássicos e alterações transitórias na anatomia retiniana externa. Paciente do sexo masculino, 20 anos de idade, apresentando embaçamento visual no olho esquerdo, relatando sintomas gripais uma semana antes do início dos sintomas visuais. Fundoscopia do olho esquerdo revelou granularidade foveal, múltiplos pontos brancos retinianos no polo posterior. A angiografia fluoresceínica e a indocianinografia verde evidenciaram achados típicos de MEWDS. A tomografia de coerência óptica de domínio espectral evidenciou alterações transitórias na anatomia retiniana externa como desaparecimento da junção dos segmentos interno-externo dos fotorreceptores e leve atenuação da membrana limitante externa. Após 6 meses, a tomografia de coerência óptica mostrou completa resolução com recuperação total da anatomia retiniana externa.

  3. Entendendo a classificação, a fisiopatologia e o diagnóstico radiológico das bronquiectasias

    Directory of Open Access Journals (Sweden)

    Bruno Hochhegger

    2010-07-01

    Full Text Available Resumo: O termo bronquiectasia é definido como uma dilatação brônquica anormal persistente geralmente associada a inflamação na via aérea e no parênquima pulmonar. A doença continua a ser uma causa comum de morbidade e mortalidade, especialmente quando associada a doenças hereditárias, como a fibrose cística, a discinesia ciliar e a alguns estados de imunodeficiência. A tomografia computadorizada é, actualmente, a modalidade de escolha para o dianóstico e pode também contribuir para o manejo clínico, sugerindo possíveis diagnósticos. Destacamos nesta revisão a classificação, a fisiopatologia e as manifestações radiológicas desta doença. Abstract: Bronchiectasis is defined as an abnormal persistent bronchial dilatation usualy associated with inflammation in the bronchial tree and lung parenchyma. The disease remains a common cause of significant morbidity and mortality, especially when associated with hereditary disorders such as cystic fibrosis, ciliary dyskinesia, and immunodeficiency states. Computed tomography is now the diagnostic modality of choice and may also contribute to clinical management, suggesting some etiologic causes. We highlight developments in classification, physiopathology and radiology of this debilitating disease. Palavras-chave: Tomografia computadorizada espiral, bronquiectasia, radiologia, fisiologia, patologia, Key-words: Tomography, spiral computed, bronchiectasis, radiology, physiology pathology

  4. Producing superfluid circulation states using phase imprinting

    Science.gov (United States)

    Kumar, Avinash; Dubessy, Romain; Badr, Thomas; De Rossi, Camilla; de Goër de Herve, Mathieu; Longchambon, Laurent; Perrin, Hélène

    2018-04-01

    We propose a method to prepare states of given quantized circulation in annular Bose-Einstein condensates (BEC) confined in a ring trap using the method of phase imprinting without relying on a two-photon angular momentum transfer. The desired phase profile is imprinted on the atomic wave function using a short light pulse with a tailored intensity pattern generated with a spatial light modulator. We demonstrate the realization of "helicoidal" intensity profiles suitable for this purpose. Due to the diffraction limit, the theoretical steplike intensity profile is not achievable in practice. We investigate the effect of imprinting an intensity profile smoothed by a finite optical resolution onto the annular BEC with a numerical simulation of the time-dependent Gross-Pitaevskii equation. This allows us to optimize the intensity pattern for a given target circulation to compensate for the limited resolution.

  5. Static elliptic minimal surfaces in AdS{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Pastras, Georgios [NCSR ' ' Demokritos' ' , Institute of Nuclear and Particle Physics, Attiki (Greece)

    2017-11-15

    The Ryu-Takayanagi conjecture connects the entanglement entropy in the boundary CFT to the area of open co-dimension two minimal surfaces in the bulk. Especially in AdS{sub 4}, the latter are two-dimensional surfaces, and, thus, solutions of a Euclidean non-linear sigma model on a symmetric target space that can be reduced to an integrable system via Pohlmeyer reduction. In this work, we construct static minimal surfaces in AdS{sub 4} that correspond to elliptic solutions of the reduced system, namely the cosh-Gordon equation, via the inversion of Pohlmeyer reduction. The constructed minimal surfaces comprise a two-parameter family of surfaces that include helicoids and catenoids in H{sup 3} as special limits. Minimal surfaces that correspond to identical boundary conditions are discovered within the constructed family of surfaces and the relevant geometric phase transitions are studied. (orig.)

  6. Quantum-mechanical generalization of the Biot-Savart law

    International Nuclear Information System (INIS)

    Fassio-Canuto, L.

    1978-01-01

    The complex geometrical considerations involved in deriving the magnetic field due to a current of assigned geometry can be considerably simplified and, therefore, generalized if one employs the field-theoretical relation between the field Asub(μ) and the current jsub(μ). In the general case of a current with helicoidal structure, the magnetic field can be found for any point of space. The particular cases of the loop, the solenoid and the straight wire are then easily derived. The rationale for wanting to generalize the classical Biot-Savart law to include quantum-mechanical effects is discussed in the light of a more general program intended to study the origin of magnetic fields in collapsed objects. (author)

  7. Focused ultrasonic wave testing, in immersion of spent fuel cans

    International Nuclear Information System (INIS)

    Poinboeuf, P.; Furlan, J.

    1984-10-01

    To detect weak and very weak damage of the fuel can, ultrasonic testing has been used. For that, a simple mechanical device, allowing to maintain an optimal ultrasonic focussing on irradiated cans, is presented. Its aim is to correct the variation of the incidence angle due to the possible ovalization of pins. After a description of the device, the results obtained with tests carried out on non-irradiated cans, including artificial ovalized regions, standard defects, are presented. After the description of the adaptation of this mechanism on a test bench which allows an helicoidal exploration of pins, some results obtained in hot cell during examinations experimental pins and previously tested by Foucault current [fr

  8. The Circulation Distribution on the Lifting Line for a Given Extracted Power

    Directory of Open Access Journals (Sweden)

    Ali Helali

    2012-01-01

    Full Text Available Presently, there exist few numerical methods which treat the inverse problem for the determination of the geometry of wind turbine blades. In this work, authors intend to solve the inverse optimum project for horizontal axis wind turbine in which the selection of the circulation distribution is obtained by resolving two variational problems: the first consists in sorting the circulation distribution on the lifting line, which, for a given power extracted by the wind turbine, minimizes the loses due to the induced velocity. In the second, the optimal circulation distribution is selected such that the kinetic energy of the wind downstream of the rotor disc is minimum, when the energy extracted by the wind turbine for one rotating period is imposed. A code has been developed which incorporates the real pitch of the helicoidal vortex wake. Very promising results have been obtained: the circulation distribution for a given extracted power and the chord lengths distribution law along the blade span.

  9. Helimagnetism and weak ferromagnetism in edge-shared chain cuprates

    International Nuclear Information System (INIS)

    Drechsler, S.-L.; Richter, J.; Kuzian, R.; Malek, J.; Tristan, N.; Buechner, B.; Moskvin, A.S.; Gippius, A.A.; Vasiliev, A.; Volkova, O.; Prokofiev, A.; Rakoto, H.; Broto, J.-M.; Schnelle, W.; Schmitt, M.; Ormeci, A.; Loison, C.; Rosner, H.

    2007-01-01

    The present understanding of a novel growing class of chain cuprates with intriguing magnetic properties is reviewed. Among them, several undoped edge-shared CuO 2 chain compounds show at low temperature a clear tendency to helicoidal magnetical ordering with acute pitch angles and sometimes also to weak ferromagnetism. Our analysis is based on the isotropic 1D frustrated J 1 -J 2 Heisenberg model with ferromagnetic (FM) 1st neighbor and antiferromagnetic 2nd neighbor exchange. The achieved assignment is supported by microscopic calculations of the electronic and magnetic structure. We consider Na(Li)Cu 2 O 2 , LiVCuO 4 as the best studied helimagnets, Li 2 ZrCuO 4 and other systems close to a FM quantum critical point, as well as Li 2 CuO 2 with FM inchain ordering. The interplay of frustrated inchain couplings, anisotropy and interchain exchange is discussed

  10. Dental TC: evaluation of the inferior dental channel

    International Nuclear Information System (INIS)

    Sanchez, F.; Carrascosa, P.; Urtube, S.; Carrascosa, J.

    2000-01-01

    To determine the location and identification of the lower dental channel (LDC) and to show the measures, guides, and different lesions that might affect it, the authors offer a retrospective and descriptive analysis of 36 CT' exams of the jaw, as a pre-implant evaluation. A Picker PQ 500 helicoidal was used. Under the 'Dental' software program, the cross-sections were reprocessed at a Voxel Q work station. The findings were divided in 3 groups: 1) Optimal visualization of the LDC in 28 patients (78%); 2) Difficult visualization of the LDC in 6 patients (16,5%); 3) The LDC was not identified in 2 patients (5,5%). Furthermore, lesions affecting the LDC were identified in 5 patients (14%) included in group 1. (author)

  11. Transitions between Taylor vortices and spirals via wavy Taylor vortices and wavy spirals

    International Nuclear Information System (INIS)

    Hoffmann, Ch; Altmeyer, S; Pinter, A; Luecke, M

    2009-01-01

    We present numerical simulations of closed wavy Taylor vortices and of helicoidal wavy spirals in the Taylor-Couette system. These wavy structures appearing via a secondary bifurcation out of Taylor vortex flow and out of spiral vortex flow, respectively, mediate transitions between Taylor and spiral vortices and vice versa. Structure, dynamics, stability and bifurcation behaviour are investigated in quantitative detail as a function of Reynolds numbers and wave numbers for counter-rotating as well as corotating cylinders. These results are obtained by solving the Navier-Stokes equations subject to axial periodicity for a radius ratio η=0.5 with a combination of a finite differences method and a Galerkin method.

  12. Self-organized internal architectures of chiral micro-particles

    International Nuclear Information System (INIS)

    Provenzano, Clementina; Mazzulla, Alfredo; Desiderio, Giovanni; Pagliusi, Pasquale; De Santo, Maria P.; Cipparrone, Gabriella; Perrotta, Ida

    2014-01-01

    The internal architecture of polymeric self-assembled chiral micro-particles is studied by exploring the effect of the chirality, of the particle sizes, and of the interface/surface properties in the ordering of the helicoidal planes. The experimental investigations, performed by means of different microscopy techniques, show that the polymeric beads, resulting from light induced polymerization of cholesteric liquid crystal droplets, preserve both the spherical shape and the internal self-organized structures. The method used to create the micro-particles with controlled internal chiral architectures presents great flexibility providing several advantages connected to the acquired optical and photonics capabilities and allowing to envisage novel strategies for the development of chiral colloidal systems and materials

  13. Koponenius gen. nov., a new genus of the millipede family Haplodesmidae from the Himalayas of India and Nepal (Diplopoda: Polydesmida).

    Science.gov (United States)

    Golovatch, Sergei I; Vandenspiegel, Didier

    2014-12-11

    The first, apparently westernmost indigenous representatives of Haplodesmidae are reported, from the Himalayas of Nepal and India. Both new species belong to a new genus, Koponenius gen. nov., with K. unicornis sp. nov., the type species from Darjeeling District, NE India, and K. biramus sp. nov., from Nepal. The new genus is superficially very similar to Prosopodesmus Silvestri, 1910, most species of which seem to be native to tropical Australia, partly also to southern Japan. However, Koponenius gen. nov. is easily distinguished in showing only 19 body segments, a special ozopore formula (5, 7-18), 4 transverse rows of setigerous isostictic tubercles per postcollum metatergum, and a clearly helicoid, twisted prefemoral portion of the gonopod so that the seminal groove runs mostly laterally, not mesally. 

  14. Intestinal mal-rotation in adults. CT findings

    International Nuclear Information System (INIS)

    Vazquez Munoz, Enrique; Ramiro Ramiro, Esther; Perez Villacastin, Benjamin; Learra Martinez, Maria C.; Franco Lopez, Maria A.

    2004-01-01

    We review 7 adult cases of intestinal mal-rotation who were studied with CT. All patients had a small bowel located in the right hemi abdomen, abnormal location of superior mesenteric vein relative to superior mesenteric artery. Superior mesenteric vein was located anteriorly and to the left of superior mesenteric artery. In patients who suffered intestinal volvulus a 'whirlpool' sign was observed, due to the helicoidal torsion of the intestine and mesentery surrounding superior mesenteric artery. In 3 cases CT demonstrated absence or poor development of the pancreas uncinate process. In 2 patients CT revealed polysplenia. CT played a major role in 3 patients with volvulus as a complication of intestinal mal-rotation. CT also demonstrated unsuspected mal-rotation in one asymptomatic patient. In 3 cases with classic symptoms CT confirmed the intestinal mal-rotation diagnosed by barium studies. (author)

  15. Avaliação da reabsorção radicular após a movimentação dentária induzida com forças contínua e contínua interrompida: análise histomorfométrica em ratos

    OpenAIRE

    Zamalloa, Yésselin Margot Miranda [UNESP

    2009-01-01

    Introdução: O propósito desta pesquisa foi avaliar a reabsorção radicular após o emprego de forças contínuas e forças contínuas interrompidas. Material e Métodos: Utilizou-se 60 ratos machos da raça Wistar divididos em dois grupos nos quais foram movimentados os primeiros molares superiores direitos com uma mola helicoidal de secção fechada de 3mm – Sentalloy- GAC, liberando 50cN de força. O Grupo I (GI) foi composto por 30 animais com Forças Contínuas (FC), Grupo II (GII), composto por 30 an...

  16. Magnetic structure of the swedenborgite CaBa (Co3Fe ) O7 derived by unpolarized neutron diffraction and spherical neutron polarimetry

    Science.gov (United States)

    Qureshi, N.; Díaz, M. T. Fernández; Chapon, L. C.; Senyshyn, A.; Schweika, W.; Valldor, M.

    2018-02-01

    We present a study that combines polarized and unpolarized neutrons to derive the magnetic structure of the swedenborgite compound CaBa (Co3Fe ) O7. Integrated intensities from a standard neutron diffraction experiment and polarization matrices from spherical neutron polarimetry have been simultaneously analyzed revealing a complex order, which differs from the usual spin configurations on a kagome lattice. We find that the magnetic structure is well described by a combination of two one-dimensional representations corresponding to the magnetic superspace symmetry P 21' , and it consists of spins rotating around an axis close to the [110] direction. Due to the propagation vector q =(1/3 00 ) , this modulation has cycloidal and helicoidal character rendering this system a potential multiferroic. The resulting spin configuration can be mapped onto the classical √{3 }×√{3 } structure of a kagome lattice, and it indicates an important interplay between the kagome and the triangular layers of the crystal structure.

  17. Review and perspectives of electrostatic turbulence and transport studies in the basic plasma physics device TORPEX

    Science.gov (United States)

    Avino, Fabio; Bovet, Alexandre; Fasoli, Ambrogio; Furno, Ivo; Gustafson, Kyle; Loizu, Joaquim; Ricci, Paolo; Theiler, Christian

    2012-10-01

    TORPEX is a basic plasma physics toroidal device located at the CRPP-EPFL in Lausanne. In TORPEX, a vertical magnetic field superposed on a toroidal field creates helicoidal field lines with both ends terminating on the torus vessel. We review recent advances in the understanding and control of electrostatic interchange turbulence, associated structures and their effect on suprathermal ions. These advances are obtained using high-resolution diagnostics of plasma parameters and wave fields throughout the whole device cross-section, fluid models and numerical simulations. Furthermore, we discuss future developments including the possibility of generating closed field line configurations with rotational transform using an internal toroidal wire carrying a current. This system will also allow the study of innovative fusion-relevant configurations, such as the snowflake divertor.

  18. [Application of three-dimensional computer graphics in oncology].

    Science.gov (United States)

    Joyeux, H; Jaeger, M; Briand, D; Servois, V; Masson, B; Borianne, P; de Reffye, P

    1996-01-01

    Accurate 3D tumoral volume evaluation is now possible through the combined use and progress of computer graphics technics (3D reconstruction and visualization) and medical imagery (helicoidal TDM scanner). Specific organ and pathology oriented softwares can help answer rapidly to problems posed by oncologic praticians. A new decision support for diagnosis, therapy and follow-up is emerging. First results in liver tumors and hepatic regeneration macroscopic biometrics are presented. Tumoral or organ volumic index will be usable in the follow-up. TNM staging, external conformal radiotherapy for prostatic or brain tumors, drugs cytolytic effects evaluation will take great advantage of these technologies. 3D visualization and matching CT and MRI imagery can help computed assisted surgery.

  19. The future of the cardiovascular image; El futuro de la imagen cardiovascular

    Energy Technology Data Exchange (ETDEWEB)

    Serna M, J A [Hospital Angeles del Pedregal, Mexico D.F. (Mexico)

    2007-07-01

    In this work the future of the cardiovascular image is presented, it is important to know the advantages and disadvantages of the current image methods to apply them in each case. The characteristics of the methods are presented: X R simple plate, the cardiac ultrasound, the image by magnetic resonance, the computed tomography, the helicoid tomography, the SPECT of myocardial perfusion, the PET and the PET/CT and the used radiopharmaceuticals. The SPECT of myocardial perfusion is the more used method around the world for the evacuation of the coronary illness. It has a high sensitivity (between 90 and 97%), it is a non-invasive treatment (morbidity of 0.01%), of relative low cost and it is useful in the diagnosis of ischemia in groups of high risk like diabetics, dyslipidemia, obese and hypertension. (Author)

  20. The future of the cardiovascular image

    International Nuclear Information System (INIS)

    Serna M, J.A.

    2007-01-01

    In this work the future of the cardiovascular image is presented, it is important to know the advantages and disadvantages of the current image methods to apply them in each case. The characteristics of the methods are presented: X R simple plate, the cardiac ultrasound, the image by magnetic resonance, the computed tomography, the helicoid tomography, the SPECT of myocardial perfusion, the PET and the PET/CT and the used radiopharmaceuticals. The SPECT of myocardial perfusion is the more used method around the world for the evacuation of the coronary illness. It has a high sensitivity (between 90 and 97%), it is a non-invasive treatment (morbidity of 0.01%), of relative low cost and it is useful in the diagnosis of ischemia in groups of high risk like diabetics, dyslipidemia, obese and hypertension. (Author)

  1. Excavación de túneles en sección total y perforación en roca

    Directory of Open Access Journals (Sweden)

    Vié, G.

    1971-09-01

    Full Text Available There is a continuous increase in the size and importance of tunnels made in connection with public works, such as motor roads, and water supply systems, and also in other fields of engineering. The author reviews the new machinery now being used to excavate full section tunnels. He studies the various types of Jumbo machinery, helicoidal screw drilling equipment. Tunnellers, and similar devices, and their suitability in various types of rock. A description is given of projects where such equipment has been utilized, and the results are evaluated. Finally, the article deals with modern type hydraulic breaking super hammers, used in rock drilling.Cada día es mayor el número y la importancia de los túneles que se realizan tanto en el sector de las obras públicas (autopistas, abastecimientos de agua... como en los demás campos de la ingeniería. El autor pasa revista a la nueva maquinaria que actualmente se utiliza en la excavación de túneles a plena sección, examinando las características de diversos tipos de jumbos, perforadoras de tornillo helicoidal, «tunnelers», y su adecuación a los diferentes terrenos. Se describen algunas realizaciones en las que han intervenido estas máquinas, analizando los resultados por ellas obtenidos. Finalmente, el artículo se ocupa de los modernos supermartillos rompedores hidráulicos empleados en la perforación en roca.

  2. Novas citações de Chytridiomycota e Oomycota para o Parque Estadual das Fontes do Ipiranga (PEFI, SP, Brasil New records of Chytridiomycota and Oomycota from the "Parque Estadual das Fontes do Ipiranga (PEFI", SP, Brazil

    Directory of Open Access Journals (Sweden)

    Carmen Lidia Amorim Pires-Zottarelli

    2007-03-01

    Full Text Available Levantamento de fungos zoospóricos realizado em lagos artificiais do Parque Estadual das Fontes do Ipiranga (PEFI, situado na cidade de São Paulo, Estado de São Paulo, Brasil, resultou no isolamento de 41 táxons, sendo 36 identificados em nível específico. Vinte e três táxons pertencem ao Reino Fungi, filo Chytridiomycota, ordens Chytridiales, Monoblepharidales e Spizellomicetales e, 18 ao Reino Straminipila, filo Oomycota, ordens Saprolegniales e Peronosporales. Dentre os fungos isolados, 14 são mencionados pela primeira vez para o PEFI: Aphanomyces helicoides von Minden, Catenochytridium kevorkianii Sparrow, Catenochytridium sp., Chytriomyces appendiculatus Karling, C. aureus Karling, C. hyalinus Karling, C. spinosus Fay, Diplophlyctis asteroidea Dogma, D. complicata (Willoughby Dogma, Karlingia dubia Karling, Nowakowskiella hemisphaerospora Shanor, Saprolegnia australis Elliott, Septochytrium variabile Berdan e Truittella sp., os quais são descritos, comentados e ilustrados. O gênero Truitella é mencionado pela primeira vez para o Brasil.A survey of zoosporic fungi from artificial lakes of the Fontes do Ipiranga State Park, in the city of São Paulo, São Paulo State, Brazil, yielded the isolation of 41 taxa with 36 species. Twenty-three taxa belong to Chytridiales, Monoblepharidales and Spizellomycetales of the Phylum Chytridiomycota, Fungi Kingdom and 18 belong to Saprolegniales and Peronosporales, Phylum Oomycota, Straminipila Kingdom. Of these, 14 are first-time records for this State Park: Aphanomyces helicoides von Minden, Catenochytridium kevorkianii Sparrow, Catenochytridium sp., Chytriomyces appendiculatus Karling, C. aureus Karling, C. hyalinus Karling, C. spinosus Fay, Diplophlyctis asteroidea Dogma, D. complicata (Willoughby Dogma, Karlingia dubia Karling, Nowakowskiella hemisphaerospora Shanor, Saprolegnia australis Elliott, Septochytrium variabile Berdan and Truittella sp., which are described, commented and

  3. Influence of twisted tape turbulence promoter on fouling reduction in microfiltration of milk proteins

    Directory of Open Access Journals (Sweden)

    Popović Svetlana S.

    2011-01-01

    Full Text Available Membrane filtration has become one of the major technologies in the food industry. It is widely applied in the dairy industry, and it is mostly used for the concentration and fractionation of milk proteins and for the whey processing. Of all pressure driven membrane processes, ultrafiltration is the most widely used. The major disadvantage of pressure driven membrane processes is severe fouling of membrane during filtration particularly when the fluids containing proteins are processed. Fouling with proteins is complex phenomenon because it occurs at the membrane surface as well as in the pores of membrane, and depends on the operating conditions and on the interactions of proteins and membrane material. In order to reduce fouling of the membrane different techniques have been developed, and one of them relies on the changing of the hydrodynamic conditions in the membrane or module. In this study, influence of twisted tape turbulence promoters on the fouling reduction in cross-flow microfiltration of skim milk was investigated. Twisted tapes with tree characteristic ratios of helix element length to the tape diameter (aspect ratio were studied. It was shown that twisted tapes with different aspect ratios reduce fouling of membrane by a factor of three or more. The presence of twisted tape induces changes in the flow patterns from straight to helicoidally thus producing turbulence flow at the lower cross-flow rates. Turbulence intensification prevents accumulation of proteins at membrane surface enabling reduction in reversible fouling what results in the reduction of overall membrane fouling. The best performance was achieved using a twisted tape with the lowest aspect ratio of 1.0. This promoter reduces fouling seven times at low transmembrane pressure and low cross-flow velocity. The twisted tape with aspect ratio 1.0 induces the most intensive turbulence, the longest helicoidal flow path, and appearance of vortices near the membrane surfaces

  4. Evolution of strike-slip fault systems and associated geomorphic structures. Model test

    International Nuclear Information System (INIS)

    Ueta, Keichi

    2003-01-01

    Sandbox experiments were performed to investigate evolution of fault systems and its associated geomorphic structures caused by strike-slip motion on basement faults. A 200 cm long, 40 cm wide, 25 cm high sandbox was used in a strike-slip fault model test. Computerized X-ray tomography applied to the sandbox experiments made it possible to analyze the kinematic evaluation, as well as the three-dimensional geometry, of the faults. The deformation of the sand pack surface was analyzed by use of a laser method 3D scanner, which is a three-dimensional noncontact surface profiling instrument. A comparison of the experimental results with natural cases of active faults reveals the following: In the left-lateral strike-slip fault experiments, the deformation of the sand pack with increasing basement displacement is observed as follows. 1) In three dimensions, the right-stepping shears that have a cirque'/'shell'/'shipbody' shape develop on both sides of the basement fault. The shears on one side of the basement fault join those on the other side, resulting in helicoidal shaped shear surfaces. Shears reach the surface of the sand near or above the basement fault and en echelon Riedel shears are observed at the surface of the sand. The region between two Riedels is always an up-squeezed block. 2) lower-angle shears generally branch off from the first Riedel shears. 3) Pressure ridges develop within the zone defined by the right-stepping helicoidal shaped lower-angle shears. 4) Grabens develop between the pressure ridges. 5) Y-shears offset the pressure ridges. 6) With displacement concentrated on the central throughgoing fault zone, a liner trough developed directly above the basement fault. R1 shear and P foliation are observed in the liner trough. Such evolution of the shears and its associated structures in the fault model tests agrees well with that of strike-slip fault systems and its associated geomorphic structures. (author)

  5. Sinal "S" de Golden

    Directory of Open Access Journals (Sweden)

    Miguel Ricardo

    2017-06-01

    Full Text Available O sinal de S Golden pode ser visto não só na radiografia do torax mas também na tomografia computorizada (TC. 1 O sinal também pode chamar-se de Sinal de S Golden Invertido porque lembra a forma de um “S” invertido.2,3 A pequena cisura, que delimita estas alterações, apresenta-se com a forma de “S” invertido, de concavidade inferior periférica, correspondente ao colapso pulmonar, e convexidade central, correspondente à massa hilar, o que pode ser apreciado na radiografia postero-anterior na TC do tórax. O lobo superior direito é o local onde mais frequentemente se desenvolvem neoplasias pulmonares, pelo que a presença do sinal “S” Golden deve levantar a suspeita de neoplasia primária.

  6. Lipo sarcoma in small intestine; Liposarcoma de intestino delgado

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Iglesias, J; Pineyro Gutierrez, A; Taroco Medeiros, L; Fein Kolodny, C; Navarrete Pedocchi, H

    1987-12-01

    A case is presented by primitive liposarcoma in small intestine , an extensive bibliographical review foreigner and national in this case. It detach the exceptional of the intestinal topography of the liposarcomas; and making stress in the relative value of the computerized tomography and ultrasonography in the diagnose of the small intestine tumors . As well as in the sarcomas of another topography, chemo and radiotherapy associated to the exeresis surgery, it can be of benefit. [Spanish] Se presenta un caso de invaginacion yeyunal por liposarcoma primitivo de intestino delgado,realizandose una extensa revision bibliografica extranjera y nacional al respecto,destacando lo exepcional de la topografia intestinal de los piposarcomas; y haciendo hincapie en lo relativo valor de la tomografia computarizada y ultrasonografia en el diagnostico de los tumores de intestino delgado.Como en los sarcomas de otra topografia,la quimio y radioterapia asociadas a la cirugia de exeresis, puede ser de beneficio.

  7. Correlação entre a Autofluorescência de Fundo e o SD-OCT na Degenerescência Macular Ligada à Idade Exsudativa

    OpenAIRE

    Miranda, Ana Filipa

    2016-01-01

    Introdução: Estudos têm mostrado que na degenerescência macular ligada à idade (DMLI) exsudativa uma maior área de alteração do epitélio pigmentar retiniano (EPR) na autofluorescência de fundo (FAF) está associada a perda da acuidade visual (AV). Não existe, no entanto, nenhum estudo realizado nestes doentes que integre as alterações verificadas na FAF com a informação anatómica da tomografia de coerência óptica spectral domain (SD-OCT). Objectivo: Investigar a correlação entre a FAF e os res...

  8. Avaliação radiográfica e tomográfica dos seios nasais de gatos com doenças sinonasais crônicas

    Directory of Open Access Journals (Sweden)

    R. Zanatta

    2011-08-01

    Full Text Available Avaliaram-se os seios nasais de 10 gatos mestiços, adultos, acometidos por afecções sinonasais, por meio de exames radiográfico e tomográfico, e descreveram-se as vantagens e desvantagens dos métodos. O grande diferencial do exame de tomografia computadorizada em relação ao exame radiográfico, na avaliação dos seios nasais, foi a detecção de alterações nos seios esfenoides e a maior facilidade em localizar a lateralidade e o grau de envolvimento de alterações dos seios frontais.

  9. Hiperplasia nodular focal do fígado: apresentação de um caso e revisão da literatura Focal nodular hyperplasia of the liver: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Marise Silva Teixeira

    2007-08-01

    Full Text Available Neste trabalho apresentamos um caso de hiperplasia nodular focal que foi diagnosticado aos seis anos de idade e que está sendo acompanhado até o momento presente. Para o diagnóstico foram imprescindíveis as técnicas de imagem, tendo importância de realce a cintilografia hepatoesplênica e a tomografia computadorizada. Apresentamos, também, revisão da literatura sobre o assunto.In this case report we discuss a focal nodular hyperplasia diagnosed in a female, six-year old patient, as well as her follow-up from the diagnosis to the present time. Imaging techniques, particularly hepatosplenic scintigraphy and computed tomography, are essential for the diagnosis. Also, a literature review is presented.

  10. Reação granulomatosa do tipo corpo estranho simulando tumor de parede torácica em cicatriz de toracotomia prévia

    Directory of Open Access Journals (Sweden)

    MACEDO NETO AMARÍLIO VIEIRA DE

    2000-01-01

    Full Text Available Paciente apresentando tumoração indolor, de crescimento lento, em local correspondente à cicatriz de toracotomia para correção de coarctação de aorta realizada 15 anos antes. Tomografia computadorizada de tórax mostrou lesões tumorais de contornos relativamente bem definidos e osteólise dos arcos costais adjacentes. Realizada ressecção e reconstrução de parede torácica. O anatomopatológico demonstrou reação de histiócitos granulares e reação granulomatosa de corpo estranho a material necro-hemorrágico. Este é um evento raro na prática médica, tendo-se realizado revisão da literatura pertinente.

  11. Herpes Zoster oftálmico e posterior acidente vascular cerebral: relato de caso

    Directory of Open Access Journals (Sweden)

    Carlos A. M. Guerreiro

    1984-12-01

    Full Text Available Um caso de acidente vascular cerebral (AVC 14 semanas após a instalação de herpes zoster oftálmico (HZO é apresentado. A tomografia computadorizada craniana documentou comprometimento em território de artéria cerebral média ipsilateral ao HZO. O diagnóstico de probabilidade é o de arterite por herpes zoster com posterior trombose. Os autores reviram a literatura e enfatizam o longo intervalo entre o HZO e a instalação da hemiplegia. Citam as novas drogas antivirais que tor