Ultrasound velocity in fixed human liver: empirical anova and regression modelling on histologically assessed abnormalities.

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

authors： Wen H

更新日期：1999-07-01 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

authors： Finette S,Bleier AR,Swindell W,Haber K

更新日期：1983-01-01 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

authors： Barber FE,Goodsitt MM

更新日期：1987-10-01 00:00:00

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

authors： Nightingale K,Bentley R,Trahey G

更新日期：2002-07-01 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

authors： Li ML,Li PC

更新日期：2003-04-01 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：: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

authors： Goldberg RL,Smith SW,Brown LF

更新日期：1992-07-01 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

authors： Ledoux LA,Brands PJ,Hoeks AP

更新日期：1997-01-01 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

authors： Sponheim N,Gelius LJ,Johansen I,Stamnes JJ

更新日期：1994-01-01 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

authors： Morrish KA,Stone M,Sonies BC,Kurtz D,Shawker T

更新日期：1984-01-01 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

authors： Emelianov SY,Lubinski MA,Skovoroda AR,Erkamp RQ,Leavey SF,Wiggins RC,O'Donnell M

更新日期：2000-07-01 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：: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：: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...

journal_title：Ultrasonic imaging

authors： Smith SW,von Ramm OT

更新日期：1988-07-01 00:00:00

abstract：:Computer texture analysis methods use texture features that are traditionally chosen from a large set of fixed features known in literature. These fixed features are often not specifically designed to the problem at hand, and as a result they may have low discriminative power, and/or may be correlated. Increasing the ...

journal_title：Ultrasonic imaging

authors： Huisman HJ,Thijssen JM

更新日期：1998-04-01 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：: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

authors： Yang JN,Murphy AD,Madsen EL,Zagzebski JA,Gilchrist KW,Frank GR,Macdonald MC,Millard CA,Faraggi A,Jaramillo CA

更新日期：1991-01-01 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：: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：:Accurate tracking of tissue motion is critically important for several ultrasound elastography methods. In this study, we investigate the feasibility of using three published convolution neural network (CNN) models built for optical flow (hereafter referred to as CNN-based tracking) by the computer vision community fo...

journal_title：Ultrasonic imaging

authors： Peng B,Xian Y,Zhang Q,Jiang J

更新日期：2020-03-01 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：: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：: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：: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

authors： Oosterveld BJ,Romijn RL,Thijssen JM

更新日期：1989-07-01 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

authors： Zandieh S,Bernt R,Zwerina J,Haller J,Knoll P,Seyeddain O,Mirzaei S

更新日期：2016-03-01 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 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

authors： Adrov VN,Chernomordik VV

更新日期：1993-01-01 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：: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