Abstract:
:In this work, we study linear array beamforming for vibro-acoustography systems. The goal of this research is to assess the feasibility of vibro-acoustography imaging systems based on linear arrays for clinical applications. The vibro-acoustography transducer is designed with two arrays driven by two continuous-wave or tone-burst signals at slightly different frequencies. The system beamforming is modeled in a homogeneous and lossless fluid. In this model, the point-spread function (psf) of the system is obtained as the product of the spatial impulse function of each linear array. Three linear array configurations are analyzed for vibro-acoustography systems. Simulations considering 64 elements in each array are performed. Aspects related to clinical applications ofvibro-acoustography, such as system spatial resolution, sidelobes, grating lobes and image frame-rate are discussed. It is concluded that linear array transducers can produce acceptable spatial resolution for clinical applications.
journal_name
Ultrason Imagingjournal_title
Ultrasonic imagingauthors
Silva GT,Greenleaf JF,Fatemi Mdoi
10.1177/016173460402600101subject
Has Abstractpub_date
2004-01-01 00:00:00pages
1-17issue
1eissn
0161-7346issn
1096-0910journal_volume
26pub_type
杂志文章abstract::Coherent speckle is a source of image noise in ultrasonic B-mode imaging. The use of multiple imaging frequencies has been suggested as a technique for speckle contrast reduction. This technique involves the averaging of images whose speckle patterns have been modified by a change in the spectrum of the transmitted or...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468600800301
更新日期:1986-07-01 00:00:00
abstract::A scalable architecture for forming real-time synthetic focus images is described and the design of a 256-channel system using currently-available technology is presented as an example implementation of the architecture. The parallelism of the system scales directly with the number of array elements and the image comp...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460302500303
更新日期:2003-07-01 00:00:00
abstract::An algorithm for deconvolution of medical ultrasound images is presented. The procedure involves estimation of the basic one-dimensional ultrasound pulse, determining the ratio of the covariance of the noise to the covariance of the reflection signal, and finally deconvolution of the rf signal from the transducer. Usi...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469301500204
更新日期:1993-04-01 00:00:00
abstract::It may be possible to diagnose and monitor scarring, inflammation and edema in transplant kidney using reconstructive ultrasound elasticity imaging. Kidney elasticity is expected to change dramatically with scar, and to a lesser degree, with acute inflammation and edema. The hypothesis that changes in kidney elasticit...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460002200303
更新日期:2000-07-01 00:00:00
abstract::A Fourier transform (FT)-based technique for forming parallel receive beams has been previously employed to increase the imaging frame rate in ultrasonic imaging. However, the image quality in FT-based parallel reconstruction is degraded because differences in range focusing delays are ignored and a wide transmit beam...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460302500201
更新日期:2003-04-01 00:00:00
abstract::Previously reported data on the temperature dependence of propagation speed in tissues generally span only temperature ranges up to 60 degrees C. However, with the emerging use of thermal ablative therapies, information on variation in this parameter over higher temperature ranges is needed. Measurements of the ultras...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460202400404
更新日期:2002-10-01 00:00:00
abstract::Mean frequency estimators as used in pulsed Doppler ultrasound equipment should provide an accurate (quality) and consistent (robustness) estimate over a wide range of signal conditions. In a simplified signal model, the main parameters to consider are the noise level, mean frequency, bandwidth and power of both the D...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469201400404
更新日期:1992-10-01 00:00:00
abstract::Conventional ultrasonic B-mode images qualitatively describe tissue structures but are unsuitable for quantitative analyses of scatterer properties. We have recently developed an ultrasonic parametric imaging technique based on the Nakagami statistical distribution that is able to quantify scatterer concentrations. Th...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460803000202
更新日期:2008-04-01 00:00:00
abstract::The propagation of pressure pulses of arbitrary time form in inhomogeneous attenuating media with characteristics similar to real biological tissues is considered. A mathematical model using the quasi-optical approximation is developed to solve the wave equation. Such a model proves to be convenient for computer reali...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469301500106
更新日期:1993-01-01 00:00:00
abstract::The aim of this study was to assess whether acoustic structure quantification (ASQ) can differentiate normal from pathological thyroid parenchyma in patients with diffuse autoimmune thyroid disease (AITD). We evaluated 83 subjects (72 [87%] women and 11 [13%] men) aged 19 to 94 years with a mean age of 53 years. We pe...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734615580766
更新日期:2016-03-01 00:00:00
abstract::Two-dimensional echocardiography (2-D echo) imaging is a more attractive clinical tool than other modalities that either involve radiation exposure or are too slow to image heart motion in real-time. Computer-aided analysis of left ventricular(LV) wall motion provides quantitative parameters for diagnosis. This study ...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469701900204
更新日期:1997-04-01 00:00:00
abstract::Breast ultrasound (BUS) imaging has become a crucial modality, especially for providing a complementary view when other modalities (i.e., mammography) are not conclusive in the task of assessing lesions. The specificity in cancer detection using BUS imaging is low. These false-positive findings often lead to an increa...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734615589287
更新日期:2016-05-01 00:00:00
abstract::Mathematical techniques are described for analyzing tongue shapes obtained with ultrasound images. The surface of the mid-sagittal section of the tongue was approximated by discrete points. In turn, these points were used to approximate position, slope and curvature of the tongue surface at a fixed time during speech....
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468400600104
更新日期:1984-01-01 00:00:00
abstract::It is well-documented in literature that benign breast lesions, such as fibroadenomas, are loosely bonded to their surrounding tissue and tend to slip under a small quasi-static compression, whereas malignant lesions being firmly bonded to their surrounding tissue do not slip. Recent developments in quasi-static ultra...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734616686746
更新日期:2017-05-01 00:00:00
abstract::In this paper, quantitative tomographic reconstructions of biological tissue are presented. First, the experimental setup and a hybrid filtered backpropagation (FBP) technique are briefly described. Using this technique, which includes exact backpropagation of data prior to reconstruction by means of the classical FBP...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469401600102
更新日期:1994-01-01 00:00:00
abstract::Regional anesthesia is preferred over general anesthesia for many surgical procedures; however, challenges associated with poor image guidance limit its widespread acceptance as a viable alternative. In B-mode ultrasound images, the current standard for guidance, nerves can be difficult to visualize due to their simil...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460903100303
更新日期:2009-07-01 00:00:00
abstract::The potential of using the phase derivative (PD) for echographic imaging was investigated. The PD data were calculated by four methods: zero crossing (ZCS) with squelch addition, analytic signal either with squelch addition (ASS) or with employment of a Wiener kernel (ASW), and unwrapped phase (UWP). The large peaks w...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468700900301
更新日期:1987-07-01 00:00:00
abstract::Ultrasonic coda wave analysis techniques localize defects in fields such as seismography and nondestructive testing. In medical ultrasound, these techniques might provide novel mapping of tissue properties in diseases characterized by local fibrosis. In this work, we present an approach for localizing variation in sca...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734619899885
更新日期:2020-01-01 00:00:00
abstract::Modern ultrasound Doppler systems are facing the problem of processing increasingly shorter data sets. Spectral analysis of the strongly nonstationary Doppler signal needs to shorten the analysis window while maintaining a low variance and high resolution spectrum. Color flow imaging requires estimation of the Doppler...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469501700101
更新日期:1995-01-01 00:00:00
abstract::Phased-array images have been obtained in vivo with a steered copolymer array operating at 2.5 MHz. The array was fabricated using 28 microns copolymer film, lambda/4 resonant at 21 MHz, which was bonded to a glass ceramic backing with a thin film bond. The 32 array elements were created by laser ablation of the conti...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469201400302
更新日期:1992-07-01 00:00:00
abstract::Anova and "dummy variables" least squares regression methods are used to investigate the dependence of ultrasound propagation velocity on the presence or absence of fat and on the rank ordered level of cirrhosis in fixed human liver. Cirrhosis is found to affect velocity in a nonlinear fashion, while fat depresses the...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468300500306
更新日期:1983-07-01 00:00:00
abstract::Tracking large deformations in tissue using ultrasound can enable the reconstruction of nonlinear elastic parameters, but poses a challenge to displacement estimation algorithms. Such large deformations have to be broken up into steps, each of which contributes an estimation error to the final accumulated displacement...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734613479246
更新日期:2013-04-01 00:00:00
abstract::An adaptive scan sequence is proposed for real-time ultrasound three-dimensional (3-D) imaging. Generally, the refresh rate of 3-D imaging is limited by the view window, resolution and sound speed in the human body. If the object is transformed or moved during the data set acquisition, the 3-D image will be distorted....
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460302500401
更新日期:2003-10-01 00:00:00
abstract::To perform computer-aided diagnosis of the thyroid nodules on ultrasound images, the location and boundary of nodules should be clearly defined. However, the identification of thyroid nodule boundary is a difficult issue due to the biological characteristics of the nodules, the physics and quality of ultrasound imagin...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734619839648
更新日期:2019-07-01 00:00:00
abstract::The liver has been hypothesized to have a unique arrangement of microvasculature that presents as an arrangement of quasiperiodic scatterers to an interrogating ultrasound pulse. The mean scatterer spacing (MSS) of these quasiperiodic scatterers has been proposed as a useful quantitative ultrasound biomarker for chara...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734613511232
更新日期:2014-04-01 00:00:00
abstract::A narrow-band ultrasonic shear-wave imaging technique for estimating phase speed was applied to fresh and thermally damaged porcine liver in vitro. Two constitutive models were applied to the measurements to represent rheological behavior of the tissue and estimate the complex shear modulus at frequencies between 50 a...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173461003200405
更新日期:2010-10-01 00:00:00
abstract::Acoustic radiation force (ARF) has become a common excitation mechanism in elasticity imaging. The high acoustic intensities and subsequent generation of harmonics, however, hamper the effectiveness of using conventional radiofrequency (rf) tracking to investigate the dynamics of tissues and catheter-based transducers...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:
更新日期:2009-01-01 00:00:00
abstract::Behavior and limitations of the sinc basis method have been discovered during simulation studies. An iterative row-action method (ART) is compared with a full-matrix, least-squares solution (QR decomposition) and the problem of multiple solutions is discussed. Knowledge of the spatial distribution of scattered field e...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468901100103
更新日期:1989-01-01 00:00:00
abstract::Our group has proposed the concept of subharmonic aided pressure estimation (SHAPE) utilizing microbubble-based ultrasound contrast agent signals for the noninvasive estimation of hydrostatic blood pressures. An experimental system for in vitro SHAPE was constructed based on two single-element transducers assembled co...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173461103300301
更新日期:2011-07-01 00:00:00
abstract::In recent years, adaptive minimum-variance (MV) beamforming has been successfully applied to medical ultrasound imaging, resulting in simultaneous improvement in imaging resolution and contrast. MV has high resolution and hence can provide accurate estimates of the target locations. However, the MV amplitude estimates...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734615600167
更新日期:2016-07-01 00:00:00