N. P. Álvarez, Mariana González, E. Budelli, P. Lema
{"title":"Dynamical characterization of a power ultrasonic bath","authors":"N. P. Álvarez, Mariana González, E. Budelli, P. Lema","doi":"10.1109/LAUS53676.2021.9639233","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639233","url":null,"abstract":"Power ultrasound has been used for many years to improve chemical and biochemical processes. As a summary, four main parameters are used to characterize an ultrasonic bath: main frequency of operation, mean delivered power, transducer type and steady state temperature. For a given process we must determine the ultrasonic power per unit of volume and the relevant parameters to predict the temperature of the process. These thermal parameters are the time constant and the heat transfer coefficient. In this work, we present a detailed study of the thermal characterization for an ultrasonic bath. We use the complete dynamical process and the response to a well-known power source to characterize the bath. This procedure is useful in the case of large systems without direct measure of the electric power delivered. This allows the determination of volumetric power delivered by the ultrasonic bath, the time constant and the loss coefficient of the bath.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114616848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
João H. Uliana, M. F. Candido, M. Brassesco, A. Carneiro, T. Pavan
{"title":"Multiangle Long-Axis Lateral Illumination Photoacoustic Imaging to Evaluate Tumor Oxygenation","authors":"João H. Uliana, M. F. Candido, M. Brassesco, A. Carneiro, T. Pavan","doi":"10.1109/LAUS53676.2021.9639188","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639188","url":null,"abstract":"Photoacoustic imaging (PAI) is an emergent technique with a wide range of biomedical applications. An interesting application of PAI is the non-invasive estimation of tissue oxygenation, which is an important parameter for early prediction of tumor response to treatment. PAI is directly affected by light fluence distribution within the target; therefore, efficient light delivery is essential to generate high quality images. Recently, we proposed a novel multiangle long-axis lateral illumination (MALLI) scheme for hand-held PAI. This new illumination strategy showed remarkable improvement in light delivery to targets smaller than the ultrasound transducer width. Subcutaneous xenograft mouse model is a typical example where the target is smaller than the transducer width. Therefore, in this study multispectral PA images were acquired from subcutaneous tumors implanted in mice with the objective to evaluate the efficiency of MALLI to map tumor vascularization and oxygen saturation (SO2). To this end, this approach was first validated acquiring multispectral PA images of tissue-mimicking phantoms. After this validation step, multispectral PA images were acquired from prostate carcinoma (PC-3) and melanoma (HT-144). The PA images clearly showed the blood vessels irrigating the tumors. For those blood vessels surrounding the tumors, a mean SO2 value of 95% was estimated, and hypoxic regions were identified within the tumor with a mean SO2 value of 86%. These results demonstrated the efficiency of MALLI-PAI to map SO2","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121848891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Durán, Ediguer E. Franco, N. Pérez, M. S. Tsuzuki, F. Buiochi
{"title":"Ultrasonic multiple-Backscattering Sensor for Monitoring of water-in-Crude Oil emulsions: Temperature Effect","authors":"A. Durán, Ediguer E. Franco, N. Pérez, M. S. Tsuzuki, F. Buiochi","doi":"10.1109/LAUS53676.2021.9639176","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639176","url":null,"abstract":"This work deals with the development of an ultrasonic backscattering sensor for the monitoring of water-in-oil emulsion. The sensor consists of a 3.5-MHz ultrasonic transducer, working in pulse-echo mode, and an array of cylindrical obstacles located in the near field. Information from the backscattering signals was extracted by two processing methods: cross-correlation and wave energy. It was studied the sensitivity of the sensor and the time stability of the emulsions at three temperatures and volume water concentration from 0% to 50%. Cross-correlation and wave energy showed dependence on concentration. However, the wave energy showed little dependence on temperature. For water content monitoring, it was observed a measurement feasibility for concentrations below 20% with the cross-correlation methods and over all the measured range of water concentrations with the wave energy methods. On the other hand, the sensor allows the measurement of the propagation velocity in the emulsion with good accuracy and in a practical way.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117317911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Santos, Giclênio C. Silva, Tiago F. Vieira, Amanda E. Silva, Ícaro B. Q. de Araújo, C. Jacinto, U. Rocha, M. S. Alexandre-Moreira, G. Silva
{"title":"Measuring cell density in a acoustofluidic microcavity","authors":"H. Santos, Giclênio C. Silva, Tiago F. Vieira, Amanda E. Silva, Ícaro B. Q. de Araújo, C. Jacinto, U. Rocha, M. S. Alexandre-Moreira, G. Silva","doi":"10.1109/LAUS53676.2021.9639224","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639224","url":null,"abstract":"Detecting changes in the density of biological cells is of paramount importance as it may reveal the cell status in processes such as differentiation and disease. Several methods have been devised to measure cell density in microfluidic devices. Here, we introduce a 3D printed microfluidic wherein cells are levitated by means of the acoustic forces of ultrasonic waves. The density can be inferred by measuring the height versus time of a single cell in free fall. We determine the density of $10mu$m-polystyrene beads and macrophage cells (line j774.A1) with high accuracy.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"2198 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130132456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparison of localization methods in super-resolution imaging","authors":"Aline Xavier, G. Pinton, David Espíndola","doi":"10.1109/LAUS53676.2021.9639191","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639191","url":null,"abstract":"Ultrasound localization microscopy (ULM) produces vascular images with a resolution ten times better than the conventional ultrasound. Generating ULM images requires several steps: injection of the microbubbles (MBs) into the bloodstream, image acquisition, detection, localization, and tracking of MBs. Finally, the accumulation of all MBs positions produces the final image. In this context, the localization step is crucial, and it is still under discussion what is the optimum localization method. In this study, four different MBs localization methods were compared using a simulation along with experimental validation in a microtube phantom. Ultrasound interactions were simulated with the FullWave Solver in a two-dimensional domain. This solver was set to simulate 1000 frames of a plane-wave propagating in a heterogeneous tissue with different diameters of vessels, containing blood and MBs flowing with a parabolic fluid velocity profile. Four methods to localize the MB were compared: Weighted centroid, 2D spline, paraboloid fitting, and onset detection. Four metrics were used to compare the methods; MB distribution error; Full-width-at-half-maximum (FWHM) error; Number of MBs detected per frame; and computational time cost. Paraboloid fitting was the most robust method, regarding different diameters. When compared to the weighted centroid, paraboloid fitting improves the estimates of the localization profile by 56%, and detects near 100% of the MBs, while weighted centroid only detected 25% of them. The precision of the onset detection method depends on the vessel diameter, showing good results only for small vessels. Most importantly, the proposed simulations can be seen as a tool that offers access to the ground truth of many MBs’ localization under relatively realistic physics.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129956548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Simulation of Temperature Distribution During HIFU Therapy Using Physics Based Deep Learning Method","authors":"Yuzhang Wang, M. Almekkawy","doi":"10.1109/LAUS53676.2021.9639152","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639152","url":null,"abstract":"Deep learning techniques has been employed recently to solve Partial Differential Equations (PDEs). A current approach known as Physics-Informed Neural Network (PINN), has evolved as a remarkable method to implement deep learning with the corresponding physics laws in the form of given linear or nonlinear PDEs. PDEs were commonly solved by using classical numerical methods like Finite Element Method or Finite Difference Method (FDM). However, it requires huge computational resources due to data set requirements, multiple dimensions or discretization. The solution of solving PDEs using PINN utilizes a mesh-free domain while still maintains high accuracy compared to conventional numerical methods. Comparing to FDM, PINN runs in less execution time with the same features and constraints. In addition, using PINN to estimate the solutions of PDEs can significantly reduce the tremendous discretized elements needed. In this paper, a PINN architecture is proposed, which employs the Bioheat Transfer Equation (BHTE) into a neural network to predict the temperature rise in a heterogeneous tissue. The thermal model simulates the heat conduction generated from the wave propagating from High Intensity Focused Ultrasound (HIFU) transducer.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122239541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Felipe Meira Ribas, J. Maia, L. Neves, A. Assef, A. Zimbico, F. Schneider, Solivan A. Valente, E. Costa
{"title":"Minimum Variance Generalized Sidelobe Canceller and Eigenspace-based Generalized Sidelobe Canceller Beamformers Combined with Frost Postfilter for Medical Ultrasound Imaging","authors":"Felipe Meira Ribas, J. Maia, L. Neves, A. Assef, A. Zimbico, F. Schneider, Solivan A. Valente, E. Costa","doi":"10.1109/LAUS53676.2021.9639164","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639164","url":null,"abstract":"There are different types of adaptive beamformers for medical ultrasound imaging using the plane waves technique. Two of these methods are relatively new, such as the Minimum Variance (MV) with Generalized Sidelobe Canceller (MVGSC) beamforming and Eigenspace-base with Generalized Sidelobe Canceller (EBGSC) beamforming. These two methods already show improvement in the ultrasound image when compared with Delay-and-Sum (DAS) beamforming and MV beamforming. In order to develop MVGSC and EBGSC techniques in this work, it was applied, to the weighted signal, the adaptive Frost postfilter. To evaluate the proposed method, two phantom data from the platform Plane-Wave Imaging Challenge in Medical Ultrasound (PICMUS) were used. One phantom with point scatterers and the other with cysts. To evaluate the performance of the beamforming with Frost postfilter we have used the Contrast Ratio (CR), the Contrast-to-Noise Ratio (CNR) and the geometric distortion ratio (GDR) of Full Width at Half Maximum (FWHM) axial and lateral. The CR and CNR were calculated in three cysts with different depths. The MVGSC-Frost and EBGSC-Frost have shown better performance than DAS, MV, MVGSC and EBGSC beamformers, but the proposed methods have a worse resolution than the others beamformers. However, it offers a much better performance in contrast, showing its potential for medical ultrasound imaging.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128238271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Parametric Study of the Subwavelength Ultrasound Beam Generated by Core-Shell Lens","authors":"Gutemberg Cardoso, J. P. Leão-Neto, J. Lopes","doi":"10.1109/LAUS53676.2021.9639192","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639192","url":null,"abstract":"Subwavelength Focused Beams (SFB) generated by Ball-Shaped lens has attracted attention of researchers due its simplicity and efficacy to overcome the diffraction limit and produce high resolution images. However, the main features of the SFB (width, length and intensity) are related with the mechanical properties of the lens and surround medium, as well as the size of the lens core and shell. To establish a detailed analysis of the SFB generated by core-shell lenses, in this work we present a parametric study of the size and mechanical properties of the lenses. To perform the numerical studies, we used the Finite Element Method (FEM) through the commercial software COMSOL Multiphysics. Our results shown that, the beams features using a Rexolite shell and fluids cores are more sensible compared with metallic cores. This result shows that they have greater versatility in terms of high-resolution applications.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133773349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nonlinearity Parameter Estimation Method in Pulse-Echo Using a Reference Phantom","authors":"Andres Coila, M. Oelze","doi":"10.1109/LAUS53676.2021.9639109","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639109","url":null,"abstract":"The nonlinearity parameter (B/A) of a fluid-like media could be useful to assess structural changes, e.g., for tissue identification. To estimate the B/A, the 2nd harmonic generated signal recorded using a dual transducer could be used. However, in many instances, only the fundamental band signal acquired, for example with a clinical linear array transducer, might be available. In our approach the 2nd harmonic is related to the depletion in the fundamental band signal when comparing echo signal envelopes collected using two different excitation pressures: low and high. Specifically, we use the energy conservation principle by relating the 2nd harmonic to the loss of power at the fundamental band as it propagates in lossy media. Our method assumes that for propagation in a lossy medium, energy from the fundamental band is transferred mainly to the 2nd harmonic, and that propagation at low power settings are quasi-linear. Data were taken from numerical phantoms by simulating a typical linear array and 3D random density media excited with a broadband 5-MHz Gaussian pulse at two excitation peak pressures, i.e., low and high of 100 kPa and 1 MPa, respectively. A well-characterized reference phantom with similar speed of sound and attenuation coefficient as the sample and known B/A was used for calibration of the unknown scattering properties of the assessed sample. An expression for estimation of the B/A of a nonuniform medium is presented. The interrogated media for testing was simulated as a nonuniform phantom with a background B/A=6 and an 18-mm diameter circular inclusion (B/A=9). The result obtained was a parametric image of the B/A versus depth that captures nonlinear changes at the location of the inclusion and below it. The results reflect the cumulative nature of the nonlinearity parameter due to the shadowing effect observed below the location of the inclusion. In summary, the method is able to derive a quantitative B/A map using a reference phantom, with potential to characterize nonlinear media with a simple pulse-echo acquisition setup.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"878 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133426095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Carlos A. B. Reyna, A. Durán, L. O. Pereira, M. S. Tsuzuki, Ediguer E. Franco, F. Buiochi
{"title":"Development of an adjustable measuring cell for ultrasonic characterization of water-in-crude oil emulsions","authors":"Carlos A. B. Reyna, A. Durán, L. O. Pereira, M. S. Tsuzuki, Ediguer E. Franco, F. Buiochi","doi":"10.1109/LAUS53676.2021.9639137","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639137","url":null,"abstract":"This work reports the experiments carried out with an adjustable measuring cell for ultrasonic characterization of water-in-crude oil emulsions. The cell prototype was designed to allow adjustments to be made to the position of the solid delay lines to avoid the overlapping echoes. The tests performed used a 0.5-MHz transducer in pulse-echo mode and emulsions with water contents ranging from 0 to 30% by volume. The echoes reflected at the interfaces of the delay lines were acquired immediately after finishing the emulsification process. Using a stirring and a peristaltic pump the flow conditions were simulated. The characterization of each emulsion was made from the reference echoes acquired in the initial experiment with an air sample. All measurements were performed at the same temperature. The results show that this technique is useful to differentiate the water-oil emulsions with water content up to 30%.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121385853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}