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DESENVOLVIMENTO DE UM SISTEMA ULTRASSÔNICO PARA CARACTERIZAÇÃO DE MATERIAIS

Ricardo Ricci Bordonal, Antonio Adilton Oliveira Carneiro, Theo Zeferino Pavan
2019 Zenodo  
Bordonal, Antonio A. O. Carneiro, Theo Z. Pavan Grupo de Inovação em Instrumentação Médica e Ultrassom, Departamento de Física, Faculdade de Fig 1.  ... 
doi:10.5281/zenodo.3473675 fatcat:kmfyudtfxjchvowo4vmq4if4nq

DESENVOLVIMENTO DE UM SISTEMA ULTRASSÔNICO PARA CARACTERIZAÇÃO DE MATERIAIS

Ricardo Ricci Bordonal, Antonio Adilton Oliveira Carneiro, Theo Zeferino Pavan
2019 Zenodo  
Este artigo apresenta um sistema para caracterização de propriedades acústicas dos materiais através do uso de métodos ultrassônicos. O sistema é capaz de garantir a estabilidade na temperatura das amostras e meio de acoplamento durante as análises, uma vez que as propriedades acústicas estão fortemente relacionadas com a temperatura dos materiais. Ambos os métodos de análise ultrassônica, pulso/eco e transmissão/recepção, são utilizados. O método de pulso/eco é utilizado na caracterização
more » ... a do meio de acoplamento e o método de transmissão/recepção é utilizado na análise das amostras dos diferentes materiais. O sistema foi avaliado com amostras de água destilada acrescidas de cloreto de sódio. Por fim foram realizadas análises com materiais a serem empregados na síntese de phantoms (simuladores de tecido biológico).
doi:10.5281/zenodo.3460996 fatcat:3tvszthuabg6rggo36fqeq5nfy

Princípios físicos da elastografia por ressonância magnética

Sílvio Leão Vieira, Lucas Nonato de Oliveira, Antonio Adilton Oliveira Carneiro
2014 Revista Brasileira de Ensino de Física  
Este trabalho constitui os primeiros esforços em apresentar ao público de língua portuguesa uma nova ferramenta, com potencial uso clínico, para estudar propriedades mecânicas de materiais e tecidos vivos. Busca-se apresentar propostas de exploração de modalidades de aquisição e processamento de imagens por ressonância magnética (IRM). A Elastografia por Ressonância Magnética (ERM) é um novo procedimento que permite a medição in vivo dos parâmetros viscoelásticos dos tecidos, e que se encontra
more » ... tualmente em fase de pesquisa. Ela baseia-se na Tomografia de Ressonância Magnética (TRM) e não usa radiação inonizante, tal como raios-X que poderiam causar dano ao tecido. A técnica de ERM funciona introduzindo-se ondas mecânicas periódicas na superfície do tecido, utilizando um atuador para excitar o meio. A introdução da onda mecânica senoidal no tecido leva a uma vibração periódica forçada, e as medições feitas pela TRM são sincronizadas com esta onda mecânica. Dessa forma é possível aumentar o contraste da imagem, que é proporcional à amplitude da onda. Assim, a tomografia por ressonância magnética funciona como uma "câmara estroboscópica" que permite a criação de um "instantâneo" da onda mecânica no tecido, sendo que a propagação de uma onda contínua pode ser utilizada para produzir um filme, tendo uma série de instantâneos em intervalos diferentes. As imagens de deslocamento de fase resultantes da propagação das ondas, através do meio, são obtidas utilizando o método de contraste de fase da técnica de imagem por RM. Estas mudanças de fase constituem a fundamentação para a posterior reconstrução dos parâmetros elásticos, que são representados por uma imagem chamada elastograma. Essa nova metodologia quantitativa e não-invasiva de propriedades elásticas de tecidos permite auxiliar os radiologistas nas decisões de diagnósticos corroborando com informações já existentes.
doi:10.1590/s1806-11172014000200001 fatcat:5x7x64yzbvcpjmaghx5x6r2l3m

Análise do equilíbrio postural estático utilizando um sistema eletromagnético tridimensional

José Ailton Oliveira Carneiro, Taiza Elaine Grespan Santos-Pontelli, José Fernando Colafêmina, Antonio Adilton Oliveira Carneiro, Eduardo Ferriolli
2010 Brazilian Journal of Otorhinolaryngology  
Earl y detection of postural disorders is essential for timely interventions in patients with imbalance. Aim: A pilot study describing a new tool for evaluating static postural balance. Study Design: A cross-sectional study of a contemporary series. Material and Method: Twenty-five volunteers (15 women and 10 men) were evaluated. The mean age was 25.8 ± 4.2 years, the mean weight was 63.9 ± 13.1Kg, the mean height was 1.68 ± 0.08 m and the body mass index was 22.3±3.3kg/m2. Posturography was
more » ... e by analysing postural sway with an electromagnetic system; a sensor was attached to the skin over the spinous process of the first thoracic vertebra. Tests were carried out with the subjects in the orthostatic position for 90 seconds, with eyes opened(EO) and closed(EC) on stable and unstable surfaces. Results: When the influence of the surface was analyzed (stable x unstable) in the EO condition, there were significant differences in the middle-lateral parameters (m-l) (p=0.004) and total path (p=0.01), and in the m-l (p=0.004) and total (p=0.014) speed. In the EC condition, there were significant differences in all parameters (p<0.001). The influence of the vision was observed in all parameters only on unstable surfaces (p<0.05). Conclusion: The new tool was efficient for analysing postural sway. Braz J Otorhinolaryngol. 2010;76(6):783-8. ORIGINAL ARTICLE
doi:10.1590/s1808-86942010000600018 fatcat:rx3k5ziivvgvnhxkyt3gunz5ya

Evaluation of postural balance in mild cognitive impairment through a three-dimensional electromagnetic system

Ana Paula Oliveira Borges, José Ailton Oliveira Carneiro, José Eduardo Zaia, Antonio Adilton Oliveira Carneiro, Osvaldo Massaiti Takayanagui
2016 Brazilian Journal of Otorhinolaryngology  
ଝ Please cite this article as: Borges APO, Carneiro JAO, Zaia JE, Carneiro AAO, Takayanagui OM.  ...  Adapted from Carneiro et al. 10 Figure 2 2 Statokinesiogram from a healthy elderly and of another with mild cognitive impairment (MCI).  ... 
doi:10.1016/j.bjorl.2015.08.023 pmid:26787112 fatcat:3z35mlkmbjbyjcrvfjpcazuo3i

Prototype of a low-cost 3D breast ultrasound imaging system

Vivian Ayres De Souza Luccas, Mehran Azimbagirad, Luciana Camargo Cabrelli, Theo Zeferino Pavan, Luiz Otavio Murta Junior, Antonio Adilton Oliveira Carneiro
2019 Zenodo  
This work describes a setup of the new acquisition system for 3D ultrasound images (i.e. B-mode) for breast tomography. Since premature and precise breast lesions diagnoses turn out in treatment more efficient and save lives, we are looking for a more precise, less painful exams and dose reduction for the patient. Therefore, a low cost scanner mechanism was built aiming to accommodate breasts under water while patient is laid down on a bed in which a robotic arm guides the ultrasound probe to
more » ... quire 2D images. Then 3D image is reconstructed using the 2D images due to render the mammary volume searching for lesions. The low cost scanner was built using a regular ultrasound machine, linear probe and major controls made by an Arduino Uno. We compared the acquired phantom images with gold standard images for mammary tissues diagnostics, i.e. Computerized Tomography and Magnetic Resonance Images. This study was evaluated using a paraffin-gel and mineral oil control phantom. Results show that the provided module is convicting enough to be used in local hospital as the next step of this study.
doi:10.5281/zenodo.3473672 fatcat:qr4xjh46grch3ilbvczq5mqrma

A pilot study on the evaluation of postural strategies in young and elderly subjects using a tridimensional electromagnetic system

José Ailton Oliveira Carneiro, Taiza Elaine Grespan Santos-Pontelli, José Fernando Colafêmina, Antonio Adilton Oliveira Carneiro, Eduardo Ferriolli
2013 Brazilian Journal of Otorhinolaryngology  
One resorts to various postural strategies while attempting to maintain balance. Objective: To assess the postural strategies adopted by young and elderly subjects in varying sensory conditions by using a system of tridimensional electromagnetic sensors positioned on the projection of the first thoracic vertebra and on the sacral region. Postural oscillation values for young and elderly subjects were also reported. Method: This observational cross-sectional study enrolled 25 young and 16
more » ... individuals. A Polhemus TM device equipped with two sensors was used to assess postural oscillation parameters (maximum displacement, mean velocity, and trajectory). Data acquisition was carried out with subjects standing while undergoing a 90-second test in four sensory conditions: eyes opened, eyes closed, on a stable surface, and on an unstable surface. Results: Sensors 1 and 2 presented significant cross-correlations in all sensory conditions for both groups (r > 0.99; p < 0.001). No statistically significant differences were seen when the crosscorrelations for both groups were compared. Conclusion: This study presented an important tool to analyze postural oscillation and assess the postural strategies of young and elderly subjects in different sensory conditions. Young and elderly individuals presented strong correlations between sensors (ankle strategy), but no statistically significant differences were seen between groups. Braz J Otorhinolaryngol. 2013;79(2):219-25. ORIGINAL ARTICLE BJORL
doi:10.5935/1808-8694.20130038 pmid:23670329 fatcat:na7pqgjjvvagfke7p5hffzagi4

Software for subjective visual vertical assessment: an observational cross-sectional study

Theo Zeferino Pavan, Martha Funabashi, José Ailton Oliveira Carneiro, Taiza Elaine Grespan dos Santos Pontelli, Walfred Tedeschi, José Fernando Colafêmina, Antonio Adilton Olivera Carneiro
2012 Brazilian Journal of Otorhinolaryngology  
A orientação espacial em relação ao eixo gravitacional é de suma importância para a manu tenção da postura, marcha e para a maioria das atividades motoras realizadas pelo ser humano. A subjetiva vertical visual é um exame que avalia a percepção individual de verticalidade. Objetivos: Os objetivos deste estudo foram: (1) desenvolver um sistema virtual para avaliar a subjetiva vertical visual, (2) produzir uma ferramenta simples para a prática clínica e (3) medir os valores da subjetiva vertical
more » ... isual em indivíduos saudáveis usando a nova ferramenta. Forma de estudo: estudo obser vacional transversal. Método: Trinta voluntários saudáveis realizaram a subjetiva vertical visual em ambas as condições, estática e dinâmica. O exame consistia em ajustar uma linha virtual na posição vertical usando o mouse do computador. Na condição estática, a linha virtual foi projetada em uma tela branca. Na condição dinâmica, círculos pretos giravam no sentido horário e anti-horário. Seis medidas foram feitas e o desvio médio em relação a vertical real, calculado. Resultados: Os desvios médios da subjetiva vertical visual foram: estática -0,372° ± 1,21; dinâmica sentido horário 1,53° ± 1,80 e dinâmica sentido anti-horário -1,11° ± 2,46. Conclusão: Este software mostrou ser prático e preciso para ser inserido na rotina de exames clínicos. Software para avaliação da subjetiva vertical visual: um estudo transversal observacional Spat ial orientation in relation to the gravitational axis is significantly important for the maintenance of the posture, gait and for most of the human's motor activities. The subjective visual vertical exam evaluates the individual's perception of vertical orientation. Objectives: The aims of this study were (1) to develop a virtual system to evaluate the subjective visual vertical exam, (2) to provide a simple tool to clinical practice and (3) to assess the subjective visual vertical values of healthy subjects using the new software. Study Design: observational cross-sectional study. Methods: Thirty healthy volunteers performed the subjective visual vertical exam in both static and dynamic conditions. The exam consisted in adjusting a virtual line in the vertical position using the computer mouse. For the static condition, the virtual line was projected in a white background. For the dynamic condition, black circles rotated in clockwise or counterclockwise directions. Six measurements were taken and the mean deviations in relation to the real vertical calculated. Results: The mean values of subjective visual vertical measurements were: static -0.372°; ± 1.21; dynamic clockwise 1.53° ± 1.80 and dynamic counterclockwise -1.11° ± 2.46. Conclusion: This software showed to be practical and accurate to be used in clinical routines. Braz J Otorhinolaryngol. 2012;78(5):51-8. Para citar este artigo, use o título em inglês BJORL Resumo Keywords: saccule and utricle, software design, vestibular function tests, vestibule, labyrinth. Palavras-chave: software, sáculo e utrículo, testes de função vestibular, vestíbulo do labirinto. ORIGINAL ARTICLE
doi:10.5935/1808-8694.20120008 pmid:23108820 fatcat:lvmqajmafzayzmhqoyrmm7i4na

Influência da obesidade e da força de preensão palmar no equilíbrio postural estático de idosas ativas

José Ailton Oliveira Carneiro, Daniel Salvini Almeida, Karla Helena Coelho Vilaça, Karina Pfrimer, Taiza Elaine Grespan Santos-Pontelli, Antonio Adilton Oliveira Carneiro, José Fernando Colafêmina, Eduardo Ferriolli
2012 Motriz: Revista de Educacao Fisica  
A velocidade média foi calculada como a razão entre a trajetória e o tempo (CARNEIRO et al., 2010) . Figura 1. Localização dos sensores eletromagnéticos. Tx: transmissor e os 3 planos.  ... 
doi:10.1590/s1980-65742012000300003 fatcat:paggprindrednnzpz7kuwubdlu

A computational tool as support in B-mode ultrasound diagnostic quality control

Antonio Carlos da Silva Senra Filho, Erbe Pandini Rodrigues, Jorge Elias Junior, Antonio Adilton Oliveira Carneiro
2014 Revista Brasileira de Engenharia Biomédica  
., 2001; British…, 1997; Mühlen, 2001; Oliveira et al., 2010) . Even with advances in the fi eld, there are still major barriers to their application in Brazil.  ... 
doi:10.1590/1517-3151.0644 fatcat:4l5cfq6itfc7dkdxtle63ndgza

A magneto-motive ultrasound platform designed for pre-clinical and clinical applications

Diego Ronaldo Thomaz Sampaio, Felipe Wilker Grillo, Alexandre Colello Bruno, Theo Zeferino Pavan, Antonio Adilton Oliveira Carneiro
2017 Research on Biomedical Engineering  
Magneto-motive ultrasound (MMUS) combines magnetism and ultrasound (US) to detect magnetic nanoparticles in soft tissues. One type of MMUS called shear-wave dispersion magneto-motive ultrasound (SDMMUS) analyzes magnetically induced shear waves (SW) to quantify the elasticity and viscosity of the medium. The lack of an established presets or protocols for pre-clinical and clinical studies currently limits the use of MMUS techniques in the clinical setting. Methods: This paper proposes a
more » ... to acquire, process, and analyze MMUS and SDMMUS data integrated with a clinical ultrasound equipment. For this purpose, we developed an easy-to-use graphical user interface, written in C++/Qt4, to create an MMUS pulse sequence and collect the ultrasonic data. We designed a graphic interface written in MATLAB to process, display, and analyze the MMUS images. To exemplify how useful the platform is, we conducted two experiments, namely (i) MMUS imaging to detect magnetic particles in the stomach of a rat, and (ii) SDMMUS to estimate the viscoelasticity of a tissue-mimicking phantom containing a spherical target of ferrite. Results: The developed software proved to be an easy-to-use platform to automate the acquisition of MMUS/SDMMUS data and image processing. In an in vivo experiment, the MMUS technique detected an area of 6.32 ± 1.32 mm 2 where magnetic particles were heterogeneously distributed in the stomach of the rat. The SDMMUS method gave elasticity and viscosity values of 5.05 ± 0.18 kPa and 2.01 ± 0.09 Pa.s, respectively, for a tissue-mimicking phantom. Conclusion: Implementation of an MMUS platform with addressed presets and protocols provides a step toward the clinical implementation of MMUS imaging equipment. This platform may help to localize magnetic particles and quantify the elasticity and viscosity of soft tissues, paving a way for its use in pre-clinical and clinical studies.
doi:10.1590/2446-4740.03116 fatcat:ojg4cd3jc5bx7ipjff74ci7gny

Neuronavegador cirúrgico guiado por imagens de ressonância magnética pré-operatória, baseado num transdutor de posição magnético

Ana Paula Perini, Lucas Ferrari de Oliveira, Rogério Bulha Siqueira, Hélio Rubens Machado, Antonio Adilton Oliveira Carneiro
2009 Revista Brasileira de Engenharia Biomédica  
.; Oliveira, L. F.; Siqueira, R. B.; Machado, H. R.; Carneiro, A. A. O.Rev. Bras. Eng. Biom., v. 25, n. 2, p. 89-100, ago. 2009Braz. J.Biom. Eng., 25(2): 89-100, 2009  ... 
doi:10.4322/rbeb.2012.069 fatcat:zbisytsllrg5hcn6z4ypgwwm4e

Photoacoustic-based thermal image formation and optimization using an evolutionary genetic algorithm

João Henrique Uliana, Diego Ronaldo Thomaz Sampaio, Antonio Adilton Oliveira Carneiro, Theo Zeferino Pavan
2018 Research on Biomedical Engineering  
Uliana JH, Sampaio DRT, Carneiro AAO, Pavan TZ Res. Biomed.  ...  Eng. 2018 June; 34(2): 147-156 155/156 Uliana JH, Sampaio DRT, Carneiro AAO,Pavan TZ Res. Biomed. Eng. 2018 June; 34(2): 147-156  ... 
doi:10.1590/2446-4740.00218 fatcat:s53bedmabjebxp4kk7qe3oyp54

Patient-specific neurosurgical phantom: assessment of visual quality, accuracy, and scaling effects

Felipe Wilker Grillo, Victor Hugo Souza, Renan Hiroshi Matsuda, Carlo Rondinoni, Theo Zeferino Pavan, Oswaldo Baffa, Helio Rubens Machado, Antonio Adilton Oliveira Carneiro
2018 3D Printing in Medicine  
Training in medical education depends on the availability of standardized materials that can reliably mimic the human anatomy and physiology. One alternative to using cadavers or animal bodies is to employ phantoms or mimicking devices. Styrene-ethylene/butylene-styrene (SEBS) gels are biologically inert and present tunable properties, including mechanical properties that resemble the soft tissue. Therefore, SEBS is an alternative to develop a patient-specific phantom, that provides real visual
more » ... and morphological experience during simulationbased neurosurgical training. Results: A 3D model was reconstructed and printed based on patient-specific magnetic resonance images. The fused deposition of polyactic acid (PLA) filament and selective laser sintering of polyamid were used for 3D printing. Silicone and SEBS materials were employed to mimic soft tissues. A neuronavigation protocol was performed on the 3D-printed models scaled to three different sizes, 100%, 50%, and 25% of the original dimensions. A neurosurgery team (17 individuals) evaluated the phantom realism as "very good" and "perfect" in 49% and 31% of the cases, respectively, and rated phantom utility as "very good" and "perfect" in 61% and 32% of the cases, respectively. Models in original size (100%) and scaled to 50% provided a quantitative and realistic visual analysis of the patient's cortical anatomy without distortion. However, reduction to one quarter of the original size (25%) hindered visualization of surface details and identification of anatomical landmarks. Conclusions: A patient-specific phantom was developed with anatomically and spatially accurate shapes, that can be used as an alternative for surgical planning. Printed models scaled to sizes that avoided quality loss might save time and reduce medical training costs.
doi:10.1186/s41205-018-0025-8 pmid:29782617 pmcid:PMC5954795 fatcat:t2ykrgjcdrcmdnfwrscwfpunuy

Reproducibility of abdominal fat assessment by ultrasound and computed tomography

Fernando Marum Mauad, Francisco Abaeté Chagas-Neto, Augusto César Garcia Saab Benedeti, Marcello Henrique Nogueira-Barbosa, Valdair Francisco Muglia, Antonio Adilton Oliveira Carneiro, Enrico Mattana Muller, Jorge Elias Junior
2017 Radiologia Brasileira  
Objective: To test the accuracy and reproducibility of ultrasound and computed tomography (CT) for the quantification of abdominal fat in correlation with the anthropometric, clinical, and biochemical assessments. Materials and Methods: Using ultrasound and CT, we determined the thickness of subcutaneous and intra-abdominal fat in 101 subjects-of whom 39 (38.6%) were men and 62 (61.4%) were women-with a mean age of 66.3 years (60-80 years). The ultrasound data were correlated with the
more » ... tric, clinical, and biochemical parameters, as well as with the areas measured by abdominal CT. Results: Intra-abdominal thickness was the variable for which the correlation with the areas of abdominal fat was strongest (i.e., the correlation coefficient was highest). We also tested the reproducibility of ultrasound and CT for the assessment of abdominal fat and found that CT measurements of abdominal fat showed greater reproducibility, having higher intraobserver and interobserver reliability than had the ultrasound measurements. There was a significant correlation between ultrasound and CT, with a correlation coefficient of 0.71. Conclusion: In the assessment of abdominal fat, the intraobserver and interobserver reliability were greater for CT than for ultrasound, although both methods showed high accuracy and good reproducibility.
doi:10.1590/0100-3984.2016.0023 pmid:28670024 pmcid:PMC5487227 fatcat:xghiqd2xojeu7jctrrqq3ebrcy
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