Abstract:
:A new online signal processing technique is described to reduce speckle noise in ultrasound images. In the imaging system, a focused piston transducer is divided into thirty-two sectors. In the receive mode, parallel signal processing arranges the sectors into eight maltese crosses. The rf signals of the perpendicular arms of each cross are multiplied in a phase sensitive process. The orthogonal receive mode multiplication is designed to reduce side lobes resulting from the sector shapes while maintaining lateral resolution through the use of the full aperture diameter. The signals from the crosses are then combined via postdetection summation. Six of the eight crosses perform successfully. The six maltese crosses show decorrelated signals equivalent to four independent samples of the speckle noise which decreases noise contrast by a factor of two with no measureable loss of spatial resolution. Post summation compression is included to retain the conventional signal dynamic range. Parallel signal processing maintains the normal image line rate. Images of tissue-mimicking phantoms including speckle targets show improved detectability of simulated lesions.
journal_name
Ultrason Imagingjournal_title
Ultrasonic imagingauthors
Smith SW,von Ramm OTdoi
10.1177/016173468801000301subject
Has Abstractpub_date
1988-07-01 00:00:00pages
153-70issue
3eissn
0161-7346issn
1096-0910journal_volume
10pub_type
杂志文章abstract::Acoustic Radiation Force Impulse (ARFI) imaging is a method for characterizing local variations in tissue mechanical properties. In this method, a single ultrasonic transducer array is used to both apply temporally short localized radiation forces within tissue and to track the resulting displacements through time. In...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460202400301
更新日期:2002-07-01 00:00:00
abstract::Time reversal of ultrasonic field allows a very efficient approach to focusing pulsed ultrasonic waves through lossless inhomogeneous media. Time reversal mirrors (TRM) are made of large transducer arrays, allowing the incident acoustic field to be sampled, time reversed and re-emitted. Time reversal processing permit...
journal_title:Ultrasonic imaging
pub_type: 杂志文章,评审
doi:10.1177/016173469601800202
更新日期:1996-04-01 00:00:00
abstract::Acoustic form factors have been used to model the frequency dependence of acoustic scattering in phantoms and tissues. This work demonstrates that a broad range of scatterer sizes, individually well represented by Faran theory or a Gaussian form factor, is not accurately described by a single effective scatterer from ...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734614534399
更新日期:2015-01-01 00:00:00
abstract::Tissues exhibiting quasi-periodic structures can be modeled as a collection of diffuse scatterers and coherent scatterers. The mean scatterer spacing (MSS) of coherent and quasi-periodic components is directly related to tissue microstructure and has become an important quantitative ultrasound (QUS) parameter in the c...
journal_title:Ultrasonic imaging
pub_type: 杂志文章,评审
doi:10.1177/0161734617692018
更新日期:2017-09-01 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::Many noninvasive ultrasound techniques have been developed to explore mechanical properties of soft tissues. One of these methods, Localized Harmonic Motion Imaging (LHMI), has been proposed to be used for ultrasound surgery monitoring. In LHMI, dynamic ultrasound radiation-force stimulation induces displacements in a...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460602800203
更新日期:2006-04-01 00:00:00
abstract::Optimal transmit phasing has been proposed to increase contrast-to-tissue ratio (CTR) by relatively phasing the tissue and leakage harmonic components to cancel each other out for tissue-background suppression in harmonic imaging. Since most clinical systems are only equipped with a bipolar square-wave pulser, effecti...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173461003200103
更新日期:2010-01-01 00:00:00
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 o...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460402600101
更新日期:2004-01-01 00:00:00
abstract::For a class of scattering objects the mean separation between the scatterers is determined. Over a range of frequencies, ultrasonic back-scattered pressure signals are recorded. It is suggested to derive the mean spacing of an unknown scattering object by employing Fourier analysis and comparing the signal with signal...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468300500405
更新日期:1983-10-01 00:00:00
abstract::Most methods for in vivo quantitation of ultrasound attenuation and backscatter are not available clinically because they rely upon acquiring and analyzing radio frequency (rf) echo signals. This paper describes a technique to estimate ultrasound attenuation and backscatter from B-mode image data. The video signal ana...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469701900305
更新日期:1997-07-01 00:00:00
abstract::In medical ultrasound imaging, two-dimensional (2-D) array transducers are desirable to implement dynamic focusing and phase aberration correction in two dimensions as well as volumetric imaging. Unfortunately, the small size of a 2-D array element results in a small clamped capacitance and a large electrical impedanc...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469501700202
更新日期:1995-04-01 00:00:00
abstract::This ex vivo study explores the relationship of ultrasonic attenuation and backscatter to dermal microarchitecture by comparing ultrasonic measurements of these parameters (11-27 MHz) to a microscopic analysis of three parameters describing the collagen distribution (mean thickness and spacing of collagen bundles alon...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460602800103
更新日期:2006-01-01 00:00:00
abstract::The methods of statistical pattern recognition have been applied to the problem of in vivo ultrasonic characterization of breast disease in humans. Backscattered A-mode signals obtained from a commercial pulse imaging system were used to generate a large set of potentially useful features. Using statistical tests, a s...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468300500107
更新日期:1983-01-01 00:00:00
abstract::The amplitude and frequency contents of a received ultrasound pulse depends on the spatial pressure amplitude distribution of the sound field, as produced by the transducer in the medium, and on the position and orientation of the reflecting surface in this field. Often, the geometry of the reflecting surface and the ...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469001200405
更新日期:1990-10-01 00:00:00
abstract::Peripheral artery disease is often asymptomatic, and various imaging and nonimaging techniques have been used for assessment and monitoring treatments. This study is designed to demonstrate the ability of photoacoustic imaging to noninvasively determine changes in tissue oxygenation that occur in mice's hind limb skel...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734619862287
更新日期:2019-09-01 00:00:00
abstract::Experimental work using a quantitative C-scan technique to measure in situ enhancement of hepatic backscatter resulting from the administration of gelatin microspheres to dogs is reported. We have found that reproducible enhancement of hepatic backscatter on the order of 2 dB followed the peripheral administration of ...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468500700402
更新日期:1985-10-01 00:00:00
abstract::When modeling or simulating an ultrasonic pulse-echo system it is necessary to know the transducer waveforms that are the input to the system. In general, accurate transducer modeling is complex and waveform calculation is computationally intensive. Because of this, investigators often assume these waveforms to be sim...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468700900405
更新日期:1987-10-01 00:00:00
abstract::Statistical pattern recognition procedures allow a quantitative description of ultrasound-B-scan image texture. According to well-established animal models, different types of fatty liver disease were induced in female Wistar rats. For the correlation of the computerized ultrasound image with its underlying histology ...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469001200302
更新日期:1990-07-01 00:00:00
abstract::Ultrasonic waveform data from a tissue-mimicking phantom containing low contrast targets was digitized, stored and processed prior to creating and displaying ultrasonic images. Speckle reduction was performed by digital filtering of the waveform data with appropriately spaced and weighted digital filters, prior to bot...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468700900202
更新日期:1987-04-01 00:00:00
abstract::The aim of this study was to identify independent risk factors for thyroid cancer, establish an ultrasonographic multimodality diagnostic model for thyroid nodules, and explore the diagnostic value of the model. From November 2011 to February 2015, 307 patients with a total of 367 thyroid nodules underwent conventiona...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734618815070
更新日期:2019-03-01 00:00:00
abstract::The microbubble contrast agent destruction/replenishment technique has been widely applied to ultrasound-based blood flow estimation. The rate of increase of the time-intensity curve (TIC) due to microbubbles flowing into the region of interest as measured from B-mode images closely reflects the flow velocity. In this...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460803000301
更新日期:2008-07-01 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::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::Hall effect imaging is an ultrasound-based method of mapping spatial variations in the dielectric constants of an acoustically-uniform sample. This paper presents three-dimensional Hall effect images of phantoms obtained by scanning a single transducer across a two-dimensional grid, effectively simulating two-dimensio...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469902100303
更新日期:1999-07-01 00:00:00
abstract::An ultrasonic imaging and signal analysis system, combining a 3.5 MHz linear array B-scanner and an array processor, has been realized for a clinical liver tissue classification study. Based on the complete unprocessed rf data set of a real time B-image, local envelope power spectra averaged over interactively defined...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469401600202
更新日期:1994-04-01 00:00:00
abstract::This paper presents a new beamforming technique, in which ultrasound waves are focused at the display pixels on the Cartesian coordinates, rather than sampling points located on the uniformly-separated scanlines on either the polar or Cartesian coordinates. Consequently, this method does not require a digital scan con...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460102300101
更新日期:2001-01-01 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::Muscle fatigue often occurs over a long period of exercise, and it can increase the risk of muscle injury. Evaluating the state of muscle fatigue can avoid unnecessary overtraining and injury of the muscle. Ultrasound imaging can non-invasively visualize muscle tissue in real-time. Image entropy is commonly used to ch...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734620952683
更新日期:2020-11-01 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::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