Performance evaluation of ultrasonic Nakagami image in tissue characterization.

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

authors： Bouchard RR,Van Soest G,Trahey GE,Van Der Steen AF

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

authors： Cavicchi TJ,O'Brien WD Jr

更新日期：1989-01-01 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

authors： Shin B,Jeon S,Ryu J,Kwon HJ

更新日期：2017-11-01 00:00:00

abstract：:The theory of diffraction tomography for two-dimensional objects within the Born approximation is presented for cases where the scattered field is measured over arbitrarily shaped boundaries surrounding the object. Reconstruction algorithms are presented for both plane wave (parallel beam) and cylindrical wave (fan be...

journal_title：Ultrasonic imaging

authors： Devaney AJ,Beylkin G

更新日期：1984-04-01 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

authors： Orescanin M,Qayyum MA,Toohey KS,Insana MF

更新日期：2010-10-01 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

authors： Lang M,Ermert H,Heuser L

更新日期：1994-04-01 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

authors： Li P,Yang X,Yin G,Guo J

更新日期：2020-11-01 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

authors： Li ML,Li PC

更新日期：2003-04-01 00:00:00

abstract：:This paper describes a method for overcoming motion artifacts in synthetic aperture imaging. The method is based on a computer simulation study on the influence of target motion on synthetic aperture techniques. A region-based motion compensation approach is used in which only the axial motion is estimated and compens...

journal_title：Ultrasonic imaging

authors： Kim KS,Hwang JS,Jeong JS,Song TK

更新日期：2002-04-01 00:00:00

abstract：:Acoustic radiation force impulse (ARFI) Surveillance of Subcutaneous Hemorrhage (ASSH) has been previously demonstrated to differentiate bleeding phenotype and responses to therapy in dogs and humans, but to date, the method has lacked experimental validation. This work explores experimental validation of ASSH in a po...

journal_title：Ultrasonic imaging

authors： Geist RE,DuBois CH,Nichols TC,Caughey MC,Merricks EP,Raymer R,Gallippi CM

更新日期：2016-09-01 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

authors： Zhao RN,Zhang B,Jiang YX,Yang X,Lai XJ,Zhu SL,Zhang XY

更新日期：2019-03-01 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

authors： Rubert N,Varghese T

更新日期：2014-04-01 00:00:00

abstract：:Attenuation measurements of various tissue mimicking phantoms and three different groups of patients were obtained using a modified commercial sector scanner. Estimates of attenuation were made using the spectral shift method with mean frequencies at different depths of a region of interest being obtained by both zero...

journal_title：Ultrasonic imaging

authors： Garra BS,Shawker TH,Nassi M,Russell MA

更新日期：1984-10-01 00:00:00

abstract：:Global and local attenuation coefficient estimations were performed in a phantom using a pulse echo method based on the rate of decay of zero crossing density. Focussed and unfocussed 3.5 MHz transducers were used. It was found that good global estimates could be made with either transducer over a 2:1 range of attenua...

journal_title：Ultrasonic imaging

authors： Ophir J,Ghouse MA,Ferrari LA

更新日期：1985-04-01 00:00:00

abstract：:Speckle noise is known to be signal-dependent in ultrasound imaging. Hence, separating noise from signal becomes a difficult task. This paper describes a wavelet-based method for reducing speckle noise. We derive from the model of the displayed ultrasound image the optimal wavelet-domain filter in the least mean-squar...

journal_title：Ultrasonic imaging

authors： Rakotomamonjy A,Deforge P,Marché P

更新日期：2000-04-01 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

authors： Romijn RL,Oosterveld BJ,Thijssen JM

更新日期：1987-07-01 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

authors： Hwang JS,Song TK

更新日期：2001-01-01 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

authors： Kirkham BM,Schultz SM,Ashi K,Sehgal CM

更新日期：2019-09-01 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

authors： Li ML,Huang SW,Ustüner K,Li PC

更新日期：2005-04-01 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

authors： Lindsey BD,Collins GC

更新日期：2020-01-01 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

authors： Knipp BS,Zagzebski JA,Wilson TA,Dong F,Madsen EL

更新日期：1997-07-01 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

authors： Li PC,Shen CC

更新日期：1999-10-01 00:00:00

abstract：:This paper addresses significant sources of electromagnetic noise in Hall effect imaging. Hall effect imaging employs large electrical pulses for signal generation and high sensitivity ultrasonic probes for signal reception. Coherent noise arises through various coupling mechanisms between the excitation pulse and the...

journal_title：Ultrasonic imaging

authors： Wen H,Bennett E,Wiesler DG

更新日期：1998-07-01 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

authors： Mohammadzadeh Asl B

更新日期：2016-07-01 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

authors： Jensen JA,Mathorne J,Gravesen T,Stage B

更新日期：1993-04-01 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

authors： Richard WD

更新日期：2003-07-01 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

authors： Linssen FM,Hoeks AP

更新日期：1990-10-01 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

authors： Chiu LY,Chen A

更新日期：2019-07-01 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

authors： Hashimoto H,Takeuchi Y

更新日期：2003-10-01 00:00:00

abstract：:An autoregressive (AR) spectral estimation method was considered for the purpose of estimating scatterer size images. The variance and bias of the resulting estimates were compared with those using classical FFT periodograms for a range of input signal-to-noise ratios and echo-signal durations corresponding to various...

journal_title：Ultrasonic imaging

authors： Chaturvedi P,Insana MF

更新日期：1996-01-01 00:00:00