Pub Date : 2023-08-21DOI: 10.1109/OJUFFC.2023.3307085
Kangfu Liu;Yaoqing Lu;Sheng Wu;Xinxin Li;Tao Wu
This work proposes the piezoelectric micromachined ultrasonic transducer (pMUT) design using high-order mode. Analytical models are established and used to estimate the performance of pMUT in ${n} ^{text {th}}$ -order axisymmetric mode. To prove the concept, a comprehensive analysis is conducted on the $3^{text {rd}}$ -order pMUT by finite element method (FEM). The analytical models give guidance for the design of electrode configuration and geometric dimensions, which are verified by FEM. With optimized electrode configuration and thickness, the proposed pMUT design shows extraordinary performance improvement in transmitting and round-trip sensitivity. Approximately $10.2times $ and $4.12times $ improvements in transmitting sensitivity and round-trip sensitivity have been achieved compared to the traditional $1^{text {st}}$ -order pMUT in the same radius, while there is an $8.6times $ improvement of the receiving voltage in the pulse-echo analysis. The high frequency, round-trip sensitivity, and directivity features of the proposed high-order pMUT design shown in FEM make it very promising for forming a high-frequency large-scale pMUT array.
{"title":"Design of Piezoelectric Micromachined Ultrasonic Transducers Using High-Order Mode With High Performance and High Frequency","authors":"Kangfu Liu;Yaoqing Lu;Sheng Wu;Xinxin Li;Tao Wu","doi":"10.1109/OJUFFC.2023.3307085","DOIUrl":"10.1109/OJUFFC.2023.3307085","url":null,"abstract":"This work proposes the piezoelectric micromachined ultrasonic transducer (pMUT) design using high-order mode. Analytical models are established and used to estimate the performance of pMUT in \u0000<inline-formula> <tex-math>${n} ^{text {th}}$ </tex-math></inline-formula>\u0000-order axisymmetric mode. To prove the concept, a comprehensive analysis is conducted on the \u0000<inline-formula> <tex-math>$3^{text {rd}}$ </tex-math></inline-formula>\u0000-order pMUT by finite element method (FEM). The analytical models give guidance for the design of electrode configuration and geometric dimensions, which are verified by FEM. With optimized electrode configuration and thickness, the proposed pMUT design shows extraordinary performance improvement in transmitting and round-trip sensitivity. Approximately \u0000<inline-formula> <tex-math>$10.2times $ </tex-math></inline-formula>\u0000 and \u0000<inline-formula> <tex-math>$4.12times $ </tex-math></inline-formula>\u0000 improvements in transmitting sensitivity and round-trip sensitivity have been achieved compared to the traditional \u0000<inline-formula> <tex-math>$1^{text {st}}$ </tex-math></inline-formula>\u0000-order pMUT in the same radius, while there is an \u0000<inline-formula> <tex-math>$8.6times $ </tex-math></inline-formula>\u0000 improvement of the receiving voltage in the pulse-echo analysis. The high frequency, round-trip sensitivity, and directivity features of the proposed high-order pMUT design shown in FEM make it very promising for forming a high-frequency large-scale pMUT array.","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"3 ","pages":"176-185"},"PeriodicalIF":0.0,"publicationDate":"2023-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10225593","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"62908847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-06DOI: 10.1109/OJUFFC.2023.3263281
{"title":"IEEE OPEN JOURNAL OF ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL","authors":"","doi":"10.1109/OJUFFC.2023.3263281","DOIUrl":"https://doi.org/10.1109/OJUFFC.2023.3263281","url":null,"abstract":"","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"3 ","pages":"C2-C2"},"PeriodicalIF":0.0,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/9292640/10031625/10174839.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49959010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-30DOI: 10.1109/OJUFFC.2023.3240699
Marta Saccher;Shinnosuke Kawasaki;Johan H. Klootwijk;Rob Van Schaijk;Ronald Dekker
Recently, the applications of ultrasound transducers expanded from high-end diagnostic tools to point of care diagnostic devices and wireless power receivers for implantable devices. These new applications additionally require that the transducer technology must comply to biocompatibility and manufacturing scalability. In this respect, Capacitive Micromachined Ultrasound Transducers (CMUTs) have a strong advantage compared to the conventional PZT based transducers. However, current CMUTs require a large DC bias voltage for their operation, which limits the miniaturizability of these devices. In this study, we propose a pre-charged collapse-mode CMUT for immersive applications that can operate without an external bias by means of a charge trapping Al2O3 layer embedded in the dielectrics between the top and bottom electrodes. The built-in charge layer was analytically modeled and four layer stack combinations were investigated and characterized. The measurement results of the CMUTs were then used to fit the model and to quantify the amount and type of trapped charge. It was found that these devices polarize due to the ferroelectric-like behavior of the Al2O3, and the amount of charge stored in the charge-trapping layer was estimated to be approximately 0.02 C/m2. Their acoustic performance shows a transmit and receive sensitivity of 8.8 kPa/V and 13.1 V/MPa respectively. In addition, we show that increasing the charging temperature, the charging duration, and the charging voltage results in a higher amount of stored charge. Finally, results of ALT tests showed that these devices have a lifetime of more than 2.5 years at body temperature.
{"title":"Modeling and Characterization of Pre-Charged Collapse-Mode CMUTs","authors":"Marta Saccher;Shinnosuke Kawasaki;Johan H. Klootwijk;Rob Van Schaijk;Ronald Dekker","doi":"10.1109/OJUFFC.2023.3240699","DOIUrl":"https://doi.org/10.1109/OJUFFC.2023.3240699","url":null,"abstract":"Recently, the applications of ultrasound transducers expanded from high-end diagnostic tools to point of care diagnostic devices and wireless power receivers for implantable devices. These new applications additionally require that the transducer technology must comply to biocompatibility and manufacturing scalability. In this respect, Capacitive Micromachined Ultrasound Transducers (CMUTs) have a strong advantage compared to the conventional PZT based transducers. However, current CMUTs require a large DC bias voltage for their operation, which limits the miniaturizability of these devices. In this study, we propose a pre-charged collapse-mode CMUT for immersive applications that can operate without an external bias by means of a charge trapping Al2O3 layer embedded in the dielectrics between the top and bottom electrodes. The built-in charge layer was analytically modeled and four layer stack combinations were investigated and characterized. The measurement results of the CMUTs were then used to fit the model and to quantify the amount and type of trapped charge. It was found that these devices polarize due to the ferroelectric-like behavior of the Al2O3, and the amount of charge stored in the charge-trapping layer was estimated to be approximately 0.02 C/m2. Their acoustic performance shows a transmit and receive sensitivity of 8.8 kPa/V and 13.1 V/MPa respectively. In addition, we show that increasing the charging temperature, the charging duration, and the charging voltage results in a higher amount of stored charge. Finally, results of ALT tests showed that these devices have a lifetime of more than 2.5 years at body temperature.","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"3 ","pages":"14-28"},"PeriodicalIF":0.0,"publicationDate":"2023-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/9292640/10031625/10029911.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49959012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.1109/OJUFFC.2023.3284781
Miho Fujieda;Motohiro Kumagai
We have developed a fiber-optic frequency and timing transfer system. It has been installed to provide timing synchronization between NICT and a distant university site connected by a 58-km urban optical fiber link. The timing signal generated at the remote site is derived from a frequency source that is stabilized using the link, and it is synchronized by a transferred timing marker. A second, separate fiber link confirms a timing synchronization uncertainty of 5.7 ns and a 10-MHz frequency instability of less than $10^{-16}$ at $10^{5}$ s averaging time. We additionally demonstrate a timing marker delivery using a code-based signal, which combines nanosecond-level uncertainty with the simplicity and compactness suitable for a system that can be deployed for synchronization across numerous sites.
{"title":"Fiber-Optic Frequency and Timing Transfer Over an Urban Optical Fiber Link","authors":"Miho Fujieda;Motohiro Kumagai","doi":"10.1109/OJUFFC.2023.3284781","DOIUrl":"https://doi.org/10.1109/OJUFFC.2023.3284781","url":null,"abstract":"We have developed a fiber-optic frequency and timing transfer system. It has been installed to provide timing synchronization between NICT and a distant university site connected by a 58-km urban optical fiber link. The timing signal generated at the remote site is derived from a frequency source that is stabilized using the link, and it is synchronized by a transferred timing marker. A second, separate fiber link confirms a timing synchronization uncertainty of 5.7 ns and a 10-MHz frequency instability of less than <inline-formula> <tex-math notation=\"LaTeX\">$10^{-16}$ </tex-math></inline-formula> at <inline-formula> <tex-math notation=\"LaTeX\">$10^{5}$ </tex-math></inline-formula> s averaging time. We additionally demonstrate a timing marker delivery using a code-based signal, which combines nanosecond-level uncertainty with the simplicity and compactness suitable for a system that can be deployed for synchronization across numerous sites.","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"3 ","pages":"70-76"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/9292640/10031625/10147246.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49930448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.1109/OJUFFC.2023.3259941
Stefano Fiorentini;Erik Andreas Rye Berg;Hans Torp;Svend Aakhus;Jørgen Avdal
Valve regurgitation is a cardiac condition caused by the incomplete closure of a cardiac valve. Untreated, this condition may result in cardiac failure. Regular monitoring of this condition is essential in guiding the decision process for surgical intervention. Current guidelines recommend a multi-parametric assessment of valve regurgitation using echocardiography, which is both time consuming and heavily dependent on the experience of the examiner. Several methods have been proposed to provide quantitative markers to facilitate the assessment of valve regurgitation, most notably the Proximal Isovelocity Surface Area (PISA) method and methods based on the quantification of the total Regurgitant Volume (RVol) from the power of backscattered blood signal. In this work, we propose a framework based on trans-thoracic 3-D high frame-rate acquisitions for the simultaneous estimation of the jet cross-sectional area and jet velocity directly at the jet core, which are then combined to estimate the instantaneous flow rate and RVol patients with aortic or mitral insufficiency. We compare two methods for the segmentation of the jet cross-sectional area from the power Doppler signal. Validation on simulated data indicates good segmentation accuracy for the best method ($beta $ = 0.97, ${R}^{{2}}$ = 0.91). Validation on recordings from a flow phantom shows good agreement ($beta $ = 1.2, ${R}^{{2}}$ = 0.88) with an external flow rate meter. Clinical feasibility of the method is also shown in a patient with mitral regurgitation.
{"title":"Quantification of Flow Rates and Flow Volumes in Valve Regurgitation Using 3-D High Frame-Rate Ultrasound","authors":"Stefano Fiorentini;Erik Andreas Rye Berg;Hans Torp;Svend Aakhus;Jørgen Avdal","doi":"10.1109/OJUFFC.2023.3259941","DOIUrl":"https://doi.org/10.1109/OJUFFC.2023.3259941","url":null,"abstract":"Valve regurgitation is a cardiac condition caused by the incomplete closure of a cardiac valve. Untreated, this condition may result in cardiac failure. Regular monitoring of this condition is essential in guiding the decision process for surgical intervention. Current guidelines recommend a multi-parametric assessment of valve regurgitation using echocardiography, which is both time consuming and heavily dependent on the experience of the examiner. Several methods have been proposed to provide quantitative markers to facilitate the assessment of valve regurgitation, most notably the Proximal Isovelocity Surface Area (PISA) method and methods based on the quantification of the total Regurgitant Volume (RVol) from the power of backscattered blood signal. In this work, we propose a framework based on trans-thoracic 3-D high frame-rate acquisitions for the simultaneous estimation of the jet cross-sectional area and jet velocity directly at the jet core, which are then combined to estimate the instantaneous flow rate and RVol patients with aortic or mitral insufficiency. We compare two methods for the segmentation of the jet cross-sectional area from the power Doppler signal. Validation on simulated data indicates good segmentation accuracy for the best method (<inline-formula> <tex-math notation=\"LaTeX\">$beta $ </tex-math></inline-formula> = 0.97, <inline-formula> <tex-math notation=\"LaTeX\">${R}^{{2}}$ </tex-math></inline-formula> = 0.91). Validation on recordings from a flow phantom shows good agreement (<inline-formula> <tex-math notation=\"LaTeX\">$beta $ </tex-math></inline-formula> = 1.2, <inline-formula> <tex-math notation=\"LaTeX\">${R}^{{2}}$ </tex-math></inline-formula> = 0.88) with an external flow rate meter. Clinical feasibility of the method is also shown in a patient with mitral regurgitation.","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"3 ","pages":"29-40"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/9292640/10031625/10077387.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49959009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sparse array designs are a promising approach to improve the beam pattern and imaging quality, especially for applications, where hardware resources are severely limited. In particular, spiral sunflower arrays become increasingly popular due to their excellent point-spread-function (PSF) characteristics and their simple, deterministic and scalable design. Therefore, several sunflower modifications for further improvement have been investigated, e.g. density tapering based on window functions adapted from apodization techniques. In this article, we introduce a two-scale spiral array design concept, which exploits the specific PSF structure of the sunflower geometry, instead of relying on window functions. The modification proposed combines two nested sunflower sub-arrays featuring two different spatial element densities such that the locations of their respective main, side and grating lobe zones differ, resulting in a balanced and improved composite one-way PSF in terms of main lobe width (MLW) and maximum side lobe level (MSLL) under far-field and narrow-band conditions. First, we provide an analysis of the unmodified classic sunflower geometry, describe its PSF zones and show how their locations in the PSF can be estimated based on the array design parameters, which finally leads to the two-scale concept. Second, we examine a specific well-matching combination of nested sub-arrays to discuss the advantages and limitations of the resulting PSF. Third, we benchmark the respective optimum arrays of the classic sunflower and density tapering strategies with the two-scale method, where the latter shows an improved performance of the one-way PSF in terms of MLW and MSLL. Fourth, the two-scale design strategy is validated using a real-world 64-element prototype for narrow-band ultrasound imaging in air. We conduct two experiments to analyze the resulting PSF and angular resolution. Overall, the results demonstrate that the proposed flexible four-parameter concept is particularly valuable for high frame rate imaging as well as for transmit-only and receive-only applications.
{"title":"Two-Scale Sparse Spiral Array Design for 3D Ultrasound Imaging in Air","authors":"Gianni Allevato;Christoph Haugwitz;Matthias Rutsch;Raphael Müller;Marius Pesavento;Mario Kupnik","doi":"10.1109/OJUFFC.2023.3303132","DOIUrl":"https://doi.org/10.1109/OJUFFC.2023.3303132","url":null,"abstract":"Sparse array designs are a promising approach to improve the beam pattern and imaging quality, especially for applications, where hardware resources are severely limited. In particular, spiral sunflower arrays become increasingly popular due to their excellent point-spread-function (PSF) characteristics and their simple, deterministic and scalable design. Therefore, several sunflower modifications for further improvement have been investigated, e.g. density tapering based on window functions adapted from apodization techniques. In this article, we introduce a two-scale spiral array design concept, which exploits the specific PSF structure of the sunflower geometry, instead of relying on window functions. The modification proposed combines two nested sunflower sub-arrays featuring two different spatial element densities such that the locations of their respective main, side and grating lobe zones differ, resulting in a balanced and improved composite one-way PSF in terms of main lobe width (MLW) and maximum side lobe level (MSLL) under far-field and narrow-band conditions. First, we provide an analysis of the unmodified classic sunflower geometry, describe its PSF zones and show how their locations in the PSF can be estimated based on the array design parameters, which finally leads to the two-scale concept. Second, we examine a specific well-matching combination of nested sub-arrays to discuss the advantages and limitations of the resulting PSF. Third, we benchmark the respective optimum arrays of the classic sunflower and density tapering strategies with the two-scale method, where the latter shows an improved performance of the one-way PSF in terms of MLW and MSLL. Fourth, the two-scale design strategy is validated using a real-world 64-element prototype for narrow-band ultrasound imaging in air. We conduct two experiments to analyze the resulting PSF and angular resolution. Overall, the results demonstrate that the proposed flexible four-parameter concept is particularly valuable for high frame rate imaging as well as for transmit-only and receive-only applications.","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"3 ","pages":"113-127"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/9292640/10031625/10210599.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49930452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.1109/OJUFFC.2023.3308486
Sebastien Salles;François Varray;Damien Garcia;Hervé Liebgott;Barbara Nicolas
Improving the image quality of 3D high-frame-rate (HFR) echocardiography has become an important research focus. Diverging Waves techniques have already shown promising results in 3D ultrasound imaging. However, phase delays induced by large tissue displacements between ultrasound transmission can deteriorate the compounding process. Motion compensation (MoCo) approaches have been introduced and integrated into the compounding process in 2-D and in 3-D simulated ultrasound volume. Here, we propose to investigate the influence of the MoCo approach on different scenarios, including several 3-D diverging wave strategies and configurations of virtual sources. First, we proposed to formalize the placement of virtual sources according to different scenarios. Then the proposed method has been tested on numerical simulations using Field II, and in vitro experimentations with a homemade rotating phantom. The nine approaches were compared quantitatively by estimating the contrast to noise (CNR) and contrast ratio (CR). The results confirmed that MoCo increased the CNR and CR for each case. On average, the MoCo algorithm increased the CNR/CR by ${mathcal {C}}$ 3.2/8.4 dB in silico, and of ${mathcal {C}}$ 1.4/1.8 dB in vitro, respectively.
{"title":"3-D High Frame Rate Imaging With Motion Compensation (3-D HFR With MoCo): An Experimental Evaluation","authors":"Sebastien Salles;François Varray;Damien Garcia;Hervé Liebgott;Barbara Nicolas","doi":"10.1109/OJUFFC.2023.3308486","DOIUrl":"https://doi.org/10.1109/OJUFFC.2023.3308486","url":null,"abstract":"Improving the image quality of 3D high-frame-rate (HFR) echocardiography has become an important research focus. Diverging Waves techniques have already shown promising results in 3D ultrasound imaging. However, phase delays induced by large tissue displacements between ultrasound transmission can deteriorate the compounding process. Motion compensation (MoCo) approaches have been introduced and integrated into the compounding process in 2-D and in 3-D simulated ultrasound volume. Here, we propose to investigate the influence of the MoCo approach on different scenarios, including several 3-D diverging wave strategies and configurations of virtual sources. First, we proposed to formalize the placement of virtual sources according to different scenarios. Then the proposed method has been tested on numerical simulations using Field II, and in vitro experimentations with a homemade rotating phantom. The nine approaches were compared quantitatively by estimating the contrast to noise (CNR) and contrast ratio (CR). The results confirmed that MoCo increased the CNR and CR for each case. On average, the MoCo algorithm increased the CNR/CR by <inline-formula> <tex-math notation=\"LaTeX\">${mathcal {C}}$ </tex-math></inline-formula>3.2/8.4 dB in silico, and of <inline-formula> <tex-math notation=\"LaTeX\">${mathcal {C}}$ </tex-math></inline-formula>1.4/1.8 dB in vitro, respectively.","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"3 ","pages":"137-145"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/9292640/10031625/10230272.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49930454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.1109/OJUFFC.2023.3274512
Alexandre Corazza;Pauline Muleki-Seya;Adrian Basarab;Barbara Nicolas
Ultrasound localization microscopy (ULM) enables the evaluation of the vascular microstructure by detecting, localizing, and tracking microbubbles (MBs) in the vascular network. ULM provides a vascular map of the network with improved spatial resolution but with an acquisition time of several minutes. Thus, it is of great importance to increase the number of MBs detected in order to limit the acquisition time. The standard MB detection method in ULM assumes that the contrast agents are the highest-intensity structures on the ultrasound images. However, in vivo data show that MB intensity may be lower than residual tissue or even noise. Thus, to facilitate the detection of these MBs, an MB detector based on decision theory is proposed in this paper. In this study, the proposed method based on the Neyman–Pearson criterion is compared with the standard intensity-based and the normalized cross-correlation detection methods on simulated and in vivo rat brain and kidney data. The new detection method makes it possible to control the false positive detection rate without degrading the MB detection rate on simulated data, to enhance the ULM vessel map resolution on in vivo brain data and to detect more vessels on in vivo kidney data.
{"title":"Microbubble Identification Based on Decision Theory for Ultrasound Localization Microscopy","authors":"Alexandre Corazza;Pauline Muleki-Seya;Adrian Basarab;Barbara Nicolas","doi":"10.1109/OJUFFC.2023.3274512","DOIUrl":"https://doi.org/10.1109/OJUFFC.2023.3274512","url":null,"abstract":"Ultrasound localization microscopy (ULM) enables the evaluation of the vascular microstructure by detecting, localizing, and tracking microbubbles (MBs) in the vascular network. ULM provides a vascular map of the network with improved spatial resolution but with an acquisition time of several minutes. Thus, it is of great importance to increase the number of MBs detected in order to limit the acquisition time. The standard MB detection method in ULM assumes that the contrast agents are the highest-intensity structures on the ultrasound images. However, in vivo data show that MB intensity may be lower than residual tissue or even noise. Thus, to facilitate the detection of these MBs, an MB detector based on decision theory is proposed in this paper. In this study, the proposed method based on the Neyman–Pearson criterion is compared with the standard intensity-based and the normalized cross-correlation detection methods on simulated and in vivo rat brain and kidney data. The new detection method makes it possible to control the false positive detection rate without degrading the MB detection rate on simulated data, to enhance the ULM vessel map resolution on in vivo brain data and to detect more vessels on in vivo kidney data.","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"3 ","pages":"41-55"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/9292640/10031625/10122512.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49959013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.1109/OJUFFC.2023.3275936
Sapna R. Bisht;Vishwas V. Trivedi;Rohit Bhardwaj;Chandan K. Jha;Debabrata Ghosh;Himanshu Shekhar
Contrast-enhanced imaging has grown significantly in the past two decades. Technology has evolved from imaging based on linear principles to elaborate pulsing and microbubble-specific detection strategies. This review provides a broad overview of the research published on these topics, emphasizing the progress made, current challenges, and future research considerations. We cover the physical and conceptual underpinnings of imaging based on ultrasound contrast agents, focused on pulsing and detection strategies. The techniques proposed are categorized according to the underlying fundamental physical and signal processing principles. We revisit methods that were previously only of academic interest and may now be clinically feasible with advances in computation and hardware. We discuss unmet challenges and opportunities originating from developments in other sub-fields of ultrasound imaging to enable wider clinical adoption of contrast-enhanced ultrasound.
{"title":"Pulsing and Detection Strategies for Contrast-Enhanced Ultrasound: A Narrative Review","authors":"Sapna R. Bisht;Vishwas V. Trivedi;Rohit Bhardwaj;Chandan K. Jha;Debabrata Ghosh;Himanshu Shekhar","doi":"10.1109/OJUFFC.2023.3275936","DOIUrl":"https://doi.org/10.1109/OJUFFC.2023.3275936","url":null,"abstract":"Contrast-enhanced imaging has grown significantly in the past two decades. Technology has evolved from imaging based on linear principles to elaborate pulsing and microbubble-specific detection strategies. This review provides a broad overview of the research published on these topics, emphasizing the progress made, current challenges, and future research considerations. We cover the physical and conceptual underpinnings of imaging based on ultrasound contrast agents, focused on pulsing and detection strategies. The techniques proposed are categorized according to the underlying fundamental physical and signal processing principles. We revisit methods that were previously only of academic interest and may now be clinically feasible with advances in computation and hardware. We discuss unmet challenges and opportunities originating from developments in other sub-fields of ultrasound imaging to enable wider clinical adoption of contrast-enhanced ultrasound.","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"3 ","pages":"56-69"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/9292640/10031625/10124036.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49959014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.1109/OJUFFC.2023.3285204
Christopher Flood;Penina Axelrad;Joanna Hinks
Low size, weight, and power (SWaP) clocks are expected to play a key role in new positioning, navigation, and timing (PNT) systems, providing augmentations or alternatives to conventional global navigation satellite systems (GNSS). Distributing high-quality PNT services from payloads with more limited resources than GNSS satellites requires signal generation from low SWaP hardware. This paper describes stable signal synthesis based on a low cost clock ensemble using software defined radio (SDR) metrology techniques and clock ensemble algorithms. First, the capacity to accurately characterize the stability of different clocks using the SDR is demonstrated. Experimental results then establish the ability to steer an oven controlled crystal oscillator (OCXO), initially to a single reference clock signal, and then to the implicit ensemble mean (IEM) of three chip scale atomic clocks (CSACs). This steered output signal has noise comparable to the short term stability of the OCXO and long term stability similar to the best clock in the ensemble.
{"title":"The Formation of a Chip Scale Atomic Clock Ensemble Using Software Defined Radios","authors":"Christopher Flood;Penina Axelrad;Joanna Hinks","doi":"10.1109/OJUFFC.2023.3285204","DOIUrl":"https://doi.org/10.1109/OJUFFC.2023.3285204","url":null,"abstract":"Low size, weight, and power (SWaP) clocks are expected to play a key role in new positioning, navigation, and timing (PNT) systems, providing augmentations or alternatives to conventional global navigation satellite systems (GNSS). Distributing high-quality PNT services from payloads with more limited resources than GNSS satellites requires signal generation from low SWaP hardware. This paper describes stable signal synthesis based on a low cost clock ensemble using software defined radio (SDR) metrology techniques and clock ensemble algorithms. First, the capacity to accurately characterize the stability of different clocks using the SDR is demonstrated. Experimental results then establish the ability to steer an oven controlled crystal oscillator (OCXO), initially to a single reference clock signal, and then to the implicit ensemble mean (IEM) of three chip scale atomic clocks (CSACs). This steered output signal has noise comparable to the short term stability of the OCXO and long term stability similar to the best clock in the ensemble.","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"3 ","pages":"77-87"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/9292640/10031625/10147872.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49930449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：