2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)最新文献_第5页

Measuring Tissue Elastic Properties Using Physics Based Neural Networks 使用基于物理的神经网络测量组织弹性特性

2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS) Pub Date : 2021-10-04 DOI: 10.1109/LAUS53676.2021.9639231

Aishwarya Mallampati, M. Almekkawy

{"title":"Measuring Tissue Elastic Properties Using Physics Based Neural Networks","authors":"Aishwarya Mallampati, M. Almekkawy","doi":"10.1109/LAUS53676.2021.9639231","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639231","url":null,"abstract":"Ultrasound elastography is a non-invasive and low-cost imaging technique that is used to detect abnormalities in soft tissues. Elastography detects solid tumors from healthy tissues by observing changes in elasticity of tissues on application of force. Reconstruction of initial tissue modulus distribution based on measured displacement/strain fields is called an inverse elasticity problem which has a wide range of applications in medical diagnosis. This paper tries to measure the elastic properties of tissues using Physics-Informed Neural Networks (PINNs). The input data consists of pre-compression and post-compression images of a phantom. Displacement and strain fields are computed from input data which are fed to our PINN model. The PINN model consists of five independent feed-forward neural networks. The model is trained using a loss function that incorporates physics laws based on linear elasticity along with the input data. Lame constants ($lambda$ and $mu$) are considered as network parameters that change during the training phase. The ground truth $lambda$ value is 920 kPa whereas the value predicted by the model is 925.319 kPa. The results indicated that that PINNs can solve inverse problems in the domain of ultrasound elastography.","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":"129469776","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}

引用次数: 5

Ultrasonic Wave Propagation for Smart Agriculture: an Arabica Coffee Case of Study 智能农业的超声波传播:以阿拉比卡咖啡为例研究

2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS) Pub Date : 2021-10-04 DOI: 10.1109/LAUS53676.2021.9639172

D. Collazos-Burbano, J. E. Cuello, M. Villagrán‐Muniz

引用次数: 3

Dielectric optical interfaces in total internal reflection for ultrasound detection 超声检测用全内反射介质光学接口

2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS) Pub Date : 2021-10-04 DOI: 10.1109/LAUS53676.2021.9639195

E. O. Carrillo Vallejo, C. G. Carreño Romano, F. Veiras, L. C. Brazzano

{"title":"Dielectric optical interfaces in total internal reflection for ultrasound detection","authors":"E. O. Carrillo Vallejo, C. G. Carreño Romano, F. Veiras, L. C. Brazzano","doi":"10.1109/LAUS53676.2021.9639195","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639195","url":null,"abstract":"In this work we carry out a detailed analysis of the design and performance of an optical quasi-point ultrasound detector for optoacoustic tomography. The detector is a two-dielectric system based on a glass prism (for light coupling) and water. The behaviour of the system is analyzed for six different modes of operation that arise from monitoring the amplitude and phase of the electric field of the reflected optical beam. For both amplitude and phase monitoring, we consider modes of operation centered on parallel and perpendicular components of the electric field individually and a differential mode (parallel-perpendicular). For each operation mode, we estimate the best set of parameters (refractive indices and angle of incidence). We verify that the optimum performance, in terms of sensitivity, is obtained when the angle of incidence of the interrogation beam is close to the critical angle. The best performance for operation modes based on monitoring an individual parameter is obtained by means of glass prisms with low refractive index, whereas for differential modes of operation higher refractive indices are preferred. We verify the linearity of each configuration by means of the numerical calculation of the total harmonic distortion","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"40 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":"130711668","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}

引用次数: 2

Improving Vibro-acoustography Images Using 2D Wavelet Transform 二维小波变换改进振动声像图

2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS) Pub Date : 2021-10-04 DOI: 10.1109/LAUS53676.2021.9639146

B. S. Marció, A. O. Carneiro, G. Braz, R. Flesch

{"title":"Improving Vibro-acoustography Images Using 2D Wavelet Transform","authors":"B. S. Marció, A. O. Carneiro, G. Braz, R. Flesch","doi":"10.1109/LAUS53676.2021.9639146","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639146","url":null,"abstract":"Vibro-acoustography is an ultrasonic technique that has demonstrated a great potential for nondestructive inspection in the last years. During the vibro-acoustography experimental tests, tone-burst excitation mode is commonly used to drive the confocal transducer. However, wave reverberation can occur and it has a potential to affect VA image quality, since reverberation generates artifacts as bright and dark fringes. This paper proposes a method based on the 2D Wavelet transform to process the images from the traditional vibro-acoustography setup and attenuate the reverberation fringes. The vibro-acoustography tests were performed in a metal sample, which presented machined circular defects on its surface. Besides the 2D Wavelet transform method, the created images were also processed using a traditional image processing approach for comparison purposes. By means of a visual inspection of the resulting images, it becomes clear that the proposed method almost attenuated the reverberation fringes. Even though the proposed method can completely remove the artifacts, the benefit is not directly observed in terms of improving the characterization of the defect diameters, since the current configuration of the proposed method also attenuates the defect contours.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"18 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":"133063745","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}

引用次数: 0

2-D mapping of optical absorber size using photoacoustic graphic equalization imaging 利用光声图形均衡成像的光学吸收器尺寸的二维映射

2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS) Pub Date : 2021-10-04 DOI: 10.1109/LAUS53676.2021.9639136

Lokesh Basavarajappa, K. Hoyt

{"title":"2-D mapping of optical absorber size using photoacoustic graphic equalization imaging","authors":"Lokesh Basavarajappa, K. Hoyt","doi":"10.1109/LAUS53676.2021.9639136","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639136","url":null,"abstract":"A new approach to photoacoustic (PA) imaging and tissue characterization is introduced. Termed PA graphic equalization (PAGE), this method divides recorded PA signals into a collection of frequency bands using a bandpass filterbank. Filter outputs are used to colorize a display. Lower frequency content depicted in the PAGE image are from smaller optical absorbers whereby higher frequency information is from larger objects. In this study, we performed simulations and experiments using homogeneous phantom materials. PA signals in radiofrequency (RF) format were simulated using MATLAB and the k-Wave toolbox (MathWorks Inc). Ultrasound (US) sensors were defined to mimic a linear array transducer. Spherical optical absorbers of diameter 8, 40, and 80 μm were defined as source elements. Simulated data was reconstructed using a time reversal method to obtain final images. Experimental PA data were obtained using a Vevo 3100 with LAZR-X system (FUJIFILM VisualSonics Inc) equipped with a MX250D linear array transducer. Experiments were performed using custom phantoms embedded with fluorescent microspheres with diameters of 10 to 45 μm or 106 to 125 μm. Simulation results from a numerical phantom containing different-sized optical absorbers of varying diameter revealed that PAGE images give insight into object size and information not provided by traditional PA images. PAGE imaging of phantoms with varying-sized optical absorbers found a 2-fold difference in mean PAGE image intensity between the two materials (p < 0.001). Conversely, PA images from these same phantoms did not exhibit any differences in intensity (p = 0.82). Overall, simulation and experimental results verified PAGE imaging can differentiate micrometer-sized optical absorbing objects of varying size.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"2015 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":"114652459","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}

引用次数: 0

Evaluation of the Standard Error of the Regression and Coefficient of Determination as goodness-of-fit parameters for Reverberant Shear Wave Elastography 作为混响横波弹性学拟合优度参数的回归标准误差和决定系数的评价

2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS) Pub Date : 2021-10-04 DOI: 10.1109/LAUS53676.2021.9639190

Aldo Tecse, Stefano Enrique Romero, B. Castañeda

引用次数: 1

Method to Depress Trailing Excitation Signal in Acoustic Well Logging 声波测井中尾尾激励信号的抑制方法

2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS) Pub Date : 2021-10-04 DOI: 10.1109/LAUS53676.2021.9639184

Kai Zhang, Xuelian Chen, Kun Zhang

引用次数: 0

Experimental study of the relationship between microbubble size and spatiotemporal pulse sequencing during super-resolution ultrasound imaging 超分辨率超声成像中微泡大小与时空脉冲序列关系的实验研究

2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS) Pub Date : 2021-10-04 DOI: 10.1109/LAUS53676.2021.9639117

Katherine G. Brown, K. Hoyt

{"title":"Experimental study of the relationship between microbubble size and spatiotemporal pulse sequencing during super-resolution ultrasound imaging","authors":"Katherine G. Brown, K. Hoyt","doi":"10.1109/LAUS53676.2021.9639117","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639117","url":null,"abstract":"Super-resolution ultrasound imaging (SR-US) has broken the ultrasound (US) diffraction limit and enabled a 10-fold improvement in spatial resolution. Clinical adoption of SR-US is currently limited in part due to long image acquisition times. This study evaluated the use of different-sized microbubbles (MBs) with nonlinear B-mode US and linear contrast-enhanced US (CEUS) imaging strategies. The main endpoint was MB detection rates. Custom US simulations using the Rayleigh-Plesset-Marmottant (RPM) model were compared to experimental US images from a vascular flow phantom. US imaging was performed using a programmable US system (Vantage 256, Verasonics Inc) equipped with an L11-4v linear array transducer and custom pulse sequencing. Four different size-isolated MBs were studied and had diameters that ranged from 1 to 2, 3 to 4, 4 to 5, or 5 to 8 $mu$ m (Advanced Microbubbles Inc). Both simulation and experimental results revealed that MB size strongly influences CEUS images and contrast-to-tissue ratio (CTR) measurements. As MB size increased beyond 2 $mu$ m, nonlinear CEUS imaging exhibited a progressive decrease in CTR values, whereas B-mode US showed the opposite trend (range 3. S to 11.2 dB). Overall, our findings reveal that SR-US image quality is considerably impacted by MB size. A combination linear B-mode US and nonlinear CEUS imaging strategy represents one solution to increase the MB detection efficiency and minimize acquisition times required for SR-US image formation. This appears particularly relevant when using polydisperse MB contrast agents like those approved clinically for human studies.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"32 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":"131490049","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}

引用次数: 1

Migration Methods with Curved Coordinate Systems 弯曲坐标系下的迁移方法

2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS) Pub Date : 2021-10-04 DOI: 10.1109/LAUS53676.2021.9639221

Sergio Sanes Negrete, J. C. Muñoz-Cuartas, K. V. van Dongen

引用次数: 0

Impact of correlation level of eigenvectors on Mean Scatterer Spacing estimation Guillermo Cortela 特征向量相关水平对平均散射体间距估计的影响

2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS) Pub Date : 2021-10-04 DOI: 10.1109/LAUS53676.2021.9639125

G. Cortela, C. Machado, C. Negreira, W. Pereira

{"title":"Impact of correlation level of eigenvectors on Mean Scatterer Spacing estimation Guillermo Cortela","authors":"G. Cortela, C. Machado, C. Negreira, W. Pereira","doi":"10.1109/LAUS53676.2021.9639125","DOIUrl":"https://doi.org/10.1109/LAUS53676.2021.9639125","url":null,"abstract":"Tissues exhibiting quasi-periodic structures are modeled as a collection of diffuse and coherent scatterers. Coherent components are quantified by mean scatterer spacing (MSS) and are closely related to tissue structure. MSS is a quantitative ultrasound parameter useful for characterizing quasi-periodic tissues and must be determined accurately. The study aims at determining the impact of correlation level (CL) of eigenvectors on MSS estimated by Singular Spectrum Analysis (SSA), compared to other spectral methods, of a periodic distribution of scatterers using backscattered ultrasound signals. Five transducers (1, 2.25, 3.5, 5 and 7.5 MHz) were used on a pulse-echo configuration. Transducers were moved parallel to the phantoms (matrix of cylindrical copper bars) to collect signals for processing with the spectral autocorrelation, SSA and quadratic transformation for MSS estimation. The sensitivity of the SSA was analyzed for CL values of 0.5, 0.6, 0.7 and 0.8. It was evidenced that as the level of correlation decreases, the sensitivity of the methods decreases. The extreme sensitivity values of the SSA technique are 0.05 (CL =0.8,7.5 MHz) and 5.5 (CL =0.5,1 MHz). For these extreme values, the MSS estimation error was 0.8% and 18% respectively, for the SSA technique.","PeriodicalId":156639,"journal":{"name":"2021 IEEE UFFC Latin America Ultrasonics Symposium (LAUS)","volume":"161 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":"127393182","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}

引用次数: 0