Pub Date : 2000-10-22DOI: 10.1109/ULTSYM.2000.922515
A. Loseu
The present paper focuses on the improvement of the dual-mode SAW (DMS) filter selectivity. The closed-form expressions, based on a simple physical model, are derived to calculate the longitudinally coupled structures of various types (2-pole and 4-pole). Tests characteristics of similar filters demonstrate a good agreement of simulations and measurements. It is shown how the system parameters may be combined to manufacture the DMS filters with an insertion loss less than 3 dB and selectivity over 36 dB.
{"title":"Double-mode SAW filters with improved selectivity","authors":"A. Loseu","doi":"10.1109/ULTSYM.2000.922515","DOIUrl":"https://doi.org/10.1109/ULTSYM.2000.922515","url":null,"abstract":"The present paper focuses on the improvement of the dual-mode SAW (DMS) filter selectivity. The closed-form expressions, based on a simple physical model, are derived to calculate the longitudinally coupled structures of various types (2-pole and 4-pole). Tests characteristics of similar filters demonstrate a good agreement of simulations and measurements. It is shown how the system parameters may be combined to manufacture the DMS filters with an insertion loss less than 3 dB and selectivity over 36 dB.","PeriodicalId":350384,"journal":{"name":"2000 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.00CH37121)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134098994","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}
Pub Date : 2000-10-22DOI: 10.1109/ULTSYM.2000.922684
H. Tamura, Y. Tomikawa
This paper deals with a vibratory gyrosensor which is constructed using only a single resonator and which can detect three-axial angular velocities. First, we propose the sensor operation principle, which can be called, "two-phase driving method for the multiaxial detection". In the next, we show a prototype sensor and its experimental results. From the experimental results, we confirmed the basic operation of the multiaxial gyrosensor.
{"title":"Three-axes vibratory gyrosensor","authors":"H. Tamura, Y. Tomikawa","doi":"10.1109/ULTSYM.2000.922684","DOIUrl":"https://doi.org/10.1109/ULTSYM.2000.922684","url":null,"abstract":"This paper deals with a vibratory gyrosensor which is constructed using only a single resonator and which can detect three-axial angular velocities. First, we propose the sensor operation principle, which can be called, \"two-phase driving method for the multiaxial detection\". In the next, we show a prototype sensor and its experimental results. From the experimental results, we confirmed the basic operation of the multiaxial gyrosensor.","PeriodicalId":350384,"journal":{"name":"2000 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.00CH37121)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127589239","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}
Pub Date : 2000-10-22DOI: 10.1109/ULTSYM.2000.921645
W.H. Chen, E. Gottlieb, J. Cannata, Y.F. Chen, K. Shung
The Ultrasound Backscatter Microscope (UBM) is a noninvasive high frequency imaging tool used frequently for imaging the eye, skin and blood vessels. Currently, most UBM systems employ a linear motor control to obtain a transverse scan. This paper reports the implementation of a UBM that performs sector scan with a servo-controlled motor to manipulate a single element transducer. The advantage of applying a sector scan versus transverse linear scan is that the transducer needs to travel less distance to acquire an image of the same area. The transducer sector movement is achieved by a brief sweep that needs only a small open area for scanning. The servomotor's sweep angle has a small are of 5 degrees and provides enough width for an image. Because of the small angle sweeping, the image can be displayed in a linear format as the image in transverse scan without further calculation. The UBM system can be operated within the 50-100 MHz frequency range. Images have been acquired with this approach on excised human eye specimen. The quality of the image compares favorably with that obtained with the conventional UBM. The results indicate that the sector scan is an alternative method for UBM scanning. Future work includes the development of a hand held probe that houses a small transducer and servomotor capable of sector scanning.
{"title":"Development of sector scanning ultrasonic backscatter microscope","authors":"W.H. Chen, E. Gottlieb, J. Cannata, Y.F. Chen, K. Shung","doi":"10.1109/ULTSYM.2000.921645","DOIUrl":"https://doi.org/10.1109/ULTSYM.2000.921645","url":null,"abstract":"The Ultrasound Backscatter Microscope (UBM) is a noninvasive high frequency imaging tool used frequently for imaging the eye, skin and blood vessels. Currently, most UBM systems employ a linear motor control to obtain a transverse scan. This paper reports the implementation of a UBM that performs sector scan with a servo-controlled motor to manipulate a single element transducer. The advantage of applying a sector scan versus transverse linear scan is that the transducer needs to travel less distance to acquire an image of the same area. The transducer sector movement is achieved by a brief sweep that needs only a small open area for scanning. The servomotor's sweep angle has a small are of 5 degrees and provides enough width for an image. Because of the small angle sweeping, the image can be displayed in a linear format as the image in transverse scan without further calculation. The UBM system can be operated within the 50-100 MHz frequency range. Images have been acquired with this approach on excised human eye specimen. The quality of the image compares favorably with that obtained with the conventional UBM. The results indicate that the sector scan is an alternative method for UBM scanning. Future work includes the development of a hand held probe that houses a small transducer and servomotor capable of sector scanning.","PeriodicalId":350384,"journal":{"name":"2000 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.00CH37121)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132602106","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}
Pub Date : 2000-10-22DOI: 10.1109/ULTSYM.2000.921539
V. Andreev, A. Oraevsky, A. Karabutov
The optoacoustic tomography (OAT) utilizes acoustic waves induced by short laser pulses in tumor with preferential light absorption. Waveform of the opto-acoustic signal detected by a wide-band transducer array provides information about shape of tumor and its specificity. The 32-element acoustic array was employed in clinical prototype of laser optoacoustic imaging system (LOIS). Piezopolymer PVDF film was used for the array transducer fabrication. Sensitivity of the array and its transient directivity pattern are discussed in this paper. The array performance was tested in experiments with phantoms.
{"title":"Wide-band acoustic pulse detection in opto-acoustic tomography system","authors":"V. Andreev, A. Oraevsky, A. Karabutov","doi":"10.1109/ULTSYM.2000.921539","DOIUrl":"https://doi.org/10.1109/ULTSYM.2000.921539","url":null,"abstract":"The optoacoustic tomography (OAT) utilizes acoustic waves induced by short laser pulses in tumor with preferential light absorption. Waveform of the opto-acoustic signal detected by a wide-band transducer array provides information about shape of tumor and its specificity. The 32-element acoustic array was employed in clinical prototype of laser optoacoustic imaging system (LOIS). Piezopolymer PVDF film was used for the array transducer fabrication. Sensitivity of the array and its transient directivity pattern are discussed in this paper. The array performance was tested in experiments with phantoms.","PeriodicalId":350384,"journal":{"name":"2000 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.00CH37121)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130687690","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}
Pub Date : 2000-10-22DOI: 10.1109/ULTSYM.2000.922607
A. Baghai-Wadji, G. Walter
We propose a new approach for the construction of wavelets based on Green's functions associated with boundary value problems. We first describe the rational behind this idea, and then present our first successful results concerning the scaling function and the wavelet associated with Laplace operator. We obtain closed form solutions for the mother wavelet and the scaling function derived from the Laplace operator. We have identified several properties of our wavelet and the associated scaling function: Each of these functions corresponds to a charge-neutral sequence of parallel lines. Our wavelet corresponds to the potential distribution of three equidistant lines with the charge densities 1,-2, and 1. Our scaling function corresponds to the element factor of an infinite array. Furthermore, we will demonstrate the existence of an infinite family of wavelet-like orthogonal systems associated with the Laplace operator. This fact guarantees great flexibilty in constructing appropriate symmetric and asymmetric bases functions. Finally we proceed to the Helmholz wave equation, and construct the scaling function and the wavelet associated with the Helmholz operator. Many of the calculations can be carried out in closed form, allowing to discuss several fascinating properties of these new functions.
{"title":"Green's function-based wavelets","authors":"A. Baghai-Wadji, G. Walter","doi":"10.1109/ULTSYM.2000.922607","DOIUrl":"https://doi.org/10.1109/ULTSYM.2000.922607","url":null,"abstract":"We propose a new approach for the construction of wavelets based on Green's functions associated with boundary value problems. We first describe the rational behind this idea, and then present our first successful results concerning the scaling function and the wavelet associated with Laplace operator. We obtain closed form solutions for the mother wavelet and the scaling function derived from the Laplace operator. We have identified several properties of our wavelet and the associated scaling function: Each of these functions corresponds to a charge-neutral sequence of parallel lines. Our wavelet corresponds to the potential distribution of three equidistant lines with the charge densities 1,-2, and 1. Our scaling function corresponds to the element factor of an infinite array. Furthermore, we will demonstrate the existence of an infinite family of wavelet-like orthogonal systems associated with the Laplace operator. This fact guarantees great flexibilty in constructing appropriate symmetric and asymmetric bases functions. Finally we proceed to the Helmholz wave equation, and construct the scaling function and the wavelet associated with the Helmholz operator. Many of the calculations can be carried out in closed form, allowing to discuss several fascinating properties of these new functions.","PeriodicalId":350384,"journal":{"name":"2000 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.00CH37121)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130796194","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}
Pub Date : 2000-10-22DOI: 10.1109/ULTSYM.2000.921669
N. Rognin, C. Merel, C. Cachard, E. Brusseau, G. Finet
Detection of endoluminal contour on IntraVascular UltraSound (IVUS) images is a determining factor for early diagnosis of pathologies like atherosclerotic plaque and dissections. Nevertheless, the echogenicity of blood and that of tissues or plaque are close, making the detection of intraluminal contour a challenging task. The purpose of this study is to obtain automatic intraluminal edge detection using ultrasound contrast agent (USCA) perfusion. In a previous study, the contribution of USCA in intravascular echography has been shown using B-scan image processing. A parametric mapping is now proposed from RF signals. The signal processing method implemented is based on the computation of time variance parameters from a sliding window applied on each RF line. A statistical study has been performed to determinate the most relevant parameter. Since USCA circulates through the intra-lumen, the time variance gives a higher value inside the lumen than in the extra-arterial medium. Parametric mapping allows endoluminal contour enhancement by reducing the speckle and increasing the SNR of 7 dB. This method is a good pre-processing procedure to improve the automatic intraluminal edge detection technique based on a deformable model approach. The IVUS system consisted of a CVIS endovascular ultrasound scanner, an ultrasound catheter with a 30 MHz, central frequency. The RF signals were acquired by a Lecroy digital scope at a sampling frequency of 200 MHz, the 4 Mbytes memory of the oscilloscope allowing the capture of 7 images of 256 scan-lines each for an investigation depth of 7 mm. In vitro experiments were conducted with a cryogel phantom mimicking artery perfused by a sodium chloride solution at a flow rate of 88 ml/min. About 0.1 ml USCA (Sonovue/sup TM/) bolus was injected into the system. With the benefit of USCA, we demonstrated the feasibility of the parametric mapping to enhance the contrast of luminal edges, and this enhancement improves the automatic intraluminal edge detection by a deformable model.
在血管内超声(IVUS)图像上检测腔内轮廓是早期诊断动脉粥样硬化斑块和夹层等病理的决定性因素。然而，血液和组织或斑块的回声性很接近，使得腔内轮廓的检测成为一项具有挑战性的任务。本研究的目的是利用超声造影剂(USCA)灌注实现腔内边缘自动检测。在先前的一项研究中，USCA在血管内超声成像中的作用已通过b扫描图像处理得到证实。现在提出了射频信号的参数映射。所实现的信号处理方法是基于应用于每条射频线的滑动窗口的时变参数的计算。已经进行了统计研究以确定最相关的参数。由于USCA在管腔内循环，因此管腔内的时间方差高于动脉外介质。参数化映射允许通过减少散斑和增加7 dB的信噪比来增强腔内轮廓。该方法是改进基于可变形模型方法的腔内边缘自动检测技术的一种很好的预处理方法。IVUS系统包括一个CVIS血管内超声扫描仪，一个中心频率为30mhz的超声导管。射频信号由Lecroy数字示波器采集，采样频率为200mhz，示波器的4mb内存允许捕获256条扫描线的7幅图像，每条扫描线的调查深度为7mm。体外实验采用低温凝胶模拟假体动脉，氯化钠溶液以88 ml/min流速灌注。系统内注射约0.1 ml USCA (Sonovue/sup TM/) bolus。利用USCA的优势，我们证明了参数映射增强腔内边缘对比度的可行性，这种增强提高了通过变形模型自动检测腔内边缘的能力。
{"title":"Ultrasound contrast agent in intravascular echography: parametric mapping based on RF output","authors":"N. Rognin, C. Merel, C. Cachard, E. Brusseau, G. Finet","doi":"10.1109/ULTSYM.2000.921669","DOIUrl":"https://doi.org/10.1109/ULTSYM.2000.921669","url":null,"abstract":"Detection of endoluminal contour on IntraVascular UltraSound (IVUS) images is a determining factor for early diagnosis of pathologies like atherosclerotic plaque and dissections. Nevertheless, the echogenicity of blood and that of tissues or plaque are close, making the detection of intraluminal contour a challenging task. The purpose of this study is to obtain automatic intraluminal edge detection using ultrasound contrast agent (USCA) perfusion. In a previous study, the contribution of USCA in intravascular echography has been shown using B-scan image processing. A parametric mapping is now proposed from RF signals. The signal processing method implemented is based on the computation of time variance parameters from a sliding window applied on each RF line. A statistical study has been performed to determinate the most relevant parameter. Since USCA circulates through the intra-lumen, the time variance gives a higher value inside the lumen than in the extra-arterial medium. Parametric mapping allows endoluminal contour enhancement by reducing the speckle and increasing the SNR of 7 dB. This method is a good pre-processing procedure to improve the automatic intraluminal edge detection technique based on a deformable model approach. The IVUS system consisted of a CVIS endovascular ultrasound scanner, an ultrasound catheter with a 30 MHz, central frequency. The RF signals were acquired by a Lecroy digital scope at a sampling frequency of 200 MHz, the 4 Mbytes memory of the oscilloscope allowing the capture of 7 images of 256 scan-lines each for an investigation depth of 7 mm. In vitro experiments were conducted with a cryogel phantom mimicking artery perfused by a sodium chloride solution at a flow rate of 88 ml/min. About 0.1 ml USCA (Sonovue/sup TM/) bolus was injected into the system. With the benefit of USCA, we demonstrated the feasibility of the parametric mapping to enhance the contrast of luminal edges, and this enhancement improves the automatic intraluminal edge detection by a deformable model.","PeriodicalId":350384,"journal":{"name":"2000 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.00CH37121)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130916344","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}
Pub Date : 2000-10-22DOI: 10.1109/ULTSYM.2000.921493
H. Robinson, E. Mclaughlin
The stress and polarization behavior of a lanthanum doped PMN-PT was evaluated using unipolar and biased drives of up to 1.3 MV/m under varying temperatures and mechanical stresses. In particular, the behavior of the strain vs. field and polarization vs. field loops for biased minor loops is be compared to that of the full unipolar drives. It is shown that, as the hysteresis of a material increases, the minor loops tend to rotate around the midline of the major loop. This leads to smaller values for the large signal piezoelectric and dielectric constants than would be predicted from the major loop alone. The behavior of several material performance measures, such as the strain energy density, electromechanical coupling factor and dielectric loss factor, are analyzed as functions of the DC bias and AC drive fields. It is shown that the energy density and coupling factor tend to increase with DC bias field but decrease with AC drive. The dielectric loss factor, on the other hand, decreases as either the DC bias or AC drive fields are increased.
{"title":"Evaluation of large signal minor loop behavior in PMN-PT ceramics","authors":"H. Robinson, E. Mclaughlin","doi":"10.1109/ULTSYM.2000.921493","DOIUrl":"https://doi.org/10.1109/ULTSYM.2000.921493","url":null,"abstract":"The stress and polarization behavior of a lanthanum doped PMN-PT was evaluated using unipolar and biased drives of up to 1.3 MV/m under varying temperatures and mechanical stresses. In particular, the behavior of the strain vs. field and polarization vs. field loops for biased minor loops is be compared to that of the full unipolar drives. It is shown that, as the hysteresis of a material increases, the minor loops tend to rotate around the midline of the major loop. This leads to smaller values for the large signal piezoelectric and dielectric constants than would be predicted from the major loop alone. The behavior of several material performance measures, such as the strain energy density, electromechanical coupling factor and dielectric loss factor, are analyzed as functions of the DC bias and AC drive fields. It is shown that the energy density and coupling factor tend to increase with DC bias field but decrease with AC drive. The dielectric loss factor, on the other hand, decreases as either the DC bias or AC drive fields are increased.","PeriodicalId":350384,"journal":{"name":"2000 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.00CH37121)","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132662674","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}
Pub Date : 2000-10-22DOI: 10.1109/ULTSYM.2000.921678
M. Insana, T. Hall, P. Chaturvedi
Acoustic properties of tissue-like media with stiff and soft scatterers were measured as a function of compressive strain up to 40%. Uniaxial strain measurements were analyzed to test the assumption that local properties of wave propagation and scattering are invariant under deformation. We found that echo spectra of gel media with soft scatterers varied significantly and predictably during compression. Specifically, centroids of Gaussian echo spectra were shifted to higher frequencies in proportion to the compressive strain applied up to 10%, and increased monotonically up to 49% at a rate depending on the scatterer size. The results explain why there is often more echo decorrelation produced in tissues than in commonly used graphite-gelatin test phantoms.
{"title":"Ultrasonic scattering in deformed media and the effects on strain imaging","authors":"M. Insana, T. Hall, P. Chaturvedi","doi":"10.1109/ULTSYM.2000.921678","DOIUrl":"https://doi.org/10.1109/ULTSYM.2000.921678","url":null,"abstract":"Acoustic properties of tissue-like media with stiff and soft scatterers were measured as a function of compressive strain up to 40%. Uniaxial strain measurements were analyzed to test the assumption that local properties of wave propagation and scattering are invariant under deformation. We found that echo spectra of gel media with soft scatterers varied significantly and predictably during compression. Specifically, centroids of Gaussian echo spectra were shifted to higher frequencies in proportion to the compressive strain applied up to 10%, and increased monotonically up to 49% at a rate depending on the scatterer size. The results explain why there is often more echo decorrelation produced in tissues than in commonly used graphite-gelatin test phantoms.","PeriodicalId":350384,"journal":{"name":"2000 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.00CH37121)","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127643674","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}
Pub Date : 2000-10-22DOI: 10.1109/ULTSYM.2000.921625
B. Porter, J. Strang, D. Rubens, K. Parker
The fusion of multiple ultrasound scans, taken from different orientations and different times, can enhance interventional procedures and can quantify response to therapy. However, fusion of ultrasound scans requires precision alignment of recognizable fiducial markers. We present the results of volume registration of liver tissue and phantom material to test the accuracy of a semi-automated registration algorithm. Both linear tracking and magnetic "Flock of Birds" (FOE) position sensing are employed to register sequential frames of 2D ultrasound into 3D space. Major vessels and/or interventional probes are utilized as internal fiducial markers for a correlation registration algorithm. US scans were obtained from a volunteer with a known hemangioma, a benign, stable, echogenic liver tumor. Complementary, non-parallel scans were then fused to determine hemangioma co-registration displacement error. The average central displacement error was 4.1 mm. To further test our algorithm, we obtained perpendicular scans of a radio-frequency (RF) ablation probe within a tissue phantom. The volumes were registered and fused successfully, with an average displacement error of 1.1 mm. In conclusion, internal structures such as vessels and interventional probes provide adequate markers for volume fusion, producing misregistration errors less than 7.4 mm.
{"title":"3D volume registration: experiments on tissue phantom and liver","authors":"B. Porter, J. Strang, D. Rubens, K. Parker","doi":"10.1109/ULTSYM.2000.921625","DOIUrl":"https://doi.org/10.1109/ULTSYM.2000.921625","url":null,"abstract":"The fusion of multiple ultrasound scans, taken from different orientations and different times, can enhance interventional procedures and can quantify response to therapy. However, fusion of ultrasound scans requires precision alignment of recognizable fiducial markers. We present the results of volume registration of liver tissue and phantom material to test the accuracy of a semi-automated registration algorithm. Both linear tracking and magnetic \"Flock of Birds\" (FOE) position sensing are employed to register sequential frames of 2D ultrasound into 3D space. Major vessels and/or interventional probes are utilized as internal fiducial markers for a correlation registration algorithm. US scans were obtained from a volunteer with a known hemangioma, a benign, stable, echogenic liver tumor. Complementary, non-parallel scans were then fused to determine hemangioma co-registration displacement error. The average central displacement error was 4.1 mm. To further test our algorithm, we obtained perpendicular scans of a radio-frequency (RF) ablation probe within a tissue phantom. The volumes were registered and fused successfully, with an average displacement error of 1.1 mm. In conclusion, internal structures such as vessels and interventional probes provide adequate markers for volume fusion, producing misregistration errors less than 7.4 mm.","PeriodicalId":350384,"journal":{"name":"2000 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.00CH37121)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127837385","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}
Pub Date : 2000-10-22DOI: 10.1109/ULTSYM.2000.921694
W. Shi, F. Forsberg, R. Bautista, C. Vecchio, R. Bernardi, B. Goldberg
An active contrast imaging enhancement technique has been developed for use with microbubble contrast agents. It employs two acoustic fields: an excitation field for conditioning microbubbles and an imaging field for detecting microbubbles. Up to 14.5 and 16 dB increases (due to microbubble conditioning) in scattered first and second harmonic signals respectively were obtained. This technique is unique for effectively enhancing the blood-to-tissue image contrast.
{"title":"Active enhancement of ultrasound contrast imaging","authors":"W. Shi, F. Forsberg, R. Bautista, C. Vecchio, R. Bernardi, B. Goldberg","doi":"10.1109/ULTSYM.2000.921694","DOIUrl":"https://doi.org/10.1109/ULTSYM.2000.921694","url":null,"abstract":"An active contrast imaging enhancement technique has been developed for use with microbubble contrast agents. It employs two acoustic fields: an excitation field for conditioning microbubbles and an imaging field for detecting microbubbles. Up to 14.5 and 16 dB increases (due to microbubble conditioning) in scattered first and second harmonic signals respectively were obtained. This technique is unique for effectively enhancing the blood-to-tissue image contrast.","PeriodicalId":350384,"journal":{"name":"2000 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.00CH37121)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115628519","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}
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