Autoregressive spectral estimation in ultrasonic scatterer size imaging.

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：: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

authors： Thomas JL,Wu F,Fink M

更新日期：1996-04-01 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

authors： Layer G,Zuna I,Lorenz A,Zerban H,Haberkorn U,Bannasch P,van Kaick G,Räth U

更新日期：1990-07-01 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：: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

authors： Herment A,Giovannelli JF

更新日期：1995-01-01 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 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：: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

authors： Bayer M,Hall TJ

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

authors： Cavicchi TJ,O'Brien WD Jr

更新日期：1989-01-01 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

authors： Tsui PH,Yeh CK,Chang CC

更新日期：2008-07-01 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：: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

authors： Nordberg EP,Hall TJ

更新日期：2015-01-01 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

authors： He P

更新日期：1988-10-01 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：: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：: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

authors： Halldorsdottir VG,Dave JK,Leodore LM,Eisenbrey JR,Park S,Hall AL,Thomenius K,Forsberg F

更新日期：2011-07-01 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

authors： Lindsey BD,Collins GC

更新日期：2020-01-01 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

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：: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

authors： Chen T,Chen TP,Tsai LM

更新日期：1997-04-01 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：: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：: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

authors： B L,Chintada BR,Thittai AK

更新日期：2017-05-01 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

authors： Palmeri ML,Dahl JJ,MacLeod DB,Grant SA,Nightingale KR

更新日期：2009-07-01 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：: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：: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：: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

authors： Zimmermann KP,Smith JC

更新日期：1983-07-01 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

authors： Trahey GE,Allison JW,Smith SW,von Ramm OT

更新日期：1986-07-01 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：: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

authors： Techavipoo U,Varghese T,Zagzebski JA,Stiles T,Frank G

更新日期：2002-10-01 00:00:00