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 both coherent and incoherent image averaging. The resultant images showed increased signal-to-target boundaries was noted in the processed, compared to unprocessed, images. Incoherent and coherent processing were investigated, and appeared to be equivalent.
journal_name
Ultrason Imagingjournal_title
Ultrasonic imagingauthors
Gehlbach SM,Sommer FGdoi
10.1177/016173468700900202subject
Has Abstractpub_date
1987-04-01 00:00:00pages
92-105issue
2eissn
0161-7346issn
1096-0910journal_volume
9pub_type
杂志文章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::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::Generation of the second harmonic signal was studied for finite amplitude distortion based harmonic imaging. Acoustic field amplitudes along the range axis of a fixed focus transducer were measured using a PVDF needle hydrophone. Results indicated that on-axis amplitudes strongly depended on the f-number at both the f...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469902100401
更新日期:1999-10-01 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::Transesophageal echocardiography (TEE) is an essential diagnostic tool in patients with poor transthoracic echocardiographic windows or when detailed imaging of structures distant from the chest wall is necessary. A real-time 3D TEE probe has been fabricated in our laboratory in order to increase the amount of informa...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460402600402
更新日期:2004-10-01 00:00:00
abstract::This study shows that the amplitude information of ultrasound echoes is carried mainly by the envelope peaks (EPs). It is first shown that the EPs in an A-line represent the maximum number of independent amplitude data. It is then demonstrated that the entire envelope could be approximately reconstructed from the EPs....
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468801000403
更新日期:1988-10-01 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::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
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::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::Sidelobe contribution from off-axis targets degrades image quality in a coherent array imaging system. In ultrasound imaging, focusing errors resulting from sound-velocity inhomogeneities in human tissue--also known as phase aberrations reduce the coherence of the received signals and elevate the sidelobe level. This ...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460502700205
更新日期:2005-04-01 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::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::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::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::A method has been developed for mapping density and ultrasonic speed in 1 mm thick slices of soft tissue with a resolution of about 1 mm. Tests using phantom sections have verified the accuracy and resolution of the ultrasonic speed maps. The method has been applied to breast tissues of three patients including tumors...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469101300105
更新日期:1991-01-01 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::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::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::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::The potential of using the phase derivative (PD) of the radio-frequency echograms for producing 2-dimensional grey scale images was further investigated. The PD images were produced by five different algorithms, which according to the results described in the companion paper yield PD images dominated by the amplitude ...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468901100301
更新日期:1989-07-01 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::Portable ultrasound is recently emerging as a new medical imaging modality featuring high portability, easy connectivity, and real-time on-site diagnostic ability. However, it does not yet provide ultrasound elastography function that enables the diagnosis of malignant lesions using elastic properties. This is mainly ...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734617716938
更新日期:2017-11-01 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::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::In pulsed Doppler ultrasound systems, the ultrasound radiofrequency (RF) signals received can be employed to estimate noninvasively the time-dependent blood velocity distribution within and artery. The RF signals are composed of signals originating from clutter (e.g., vessel walls) and scatterers (e.g., red blood cell...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469701900101
更新日期:1997-01-01 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::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::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