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 ultrasonic propagation speed and attenuation in tissue in vitro at discrete temperatures ranging from 25 to 95 degrees C was performed for canine liver, muscle, kidney and prostate using 3 and 5 MHz center frequencies. The objective was to produce information for calibrating temperature-monitoring algorithms during ablative therapy. Resulting curves of the propagation speed vs. temperature for these tissues can be divided into three regions. In the 25-40 degrees C range, the speed of sound increase rapidly with temperature. It increases moderately with temperature in the 40-70 degrees C range, and it then decreases with increasing temperature from 70-95 degrees C. Attenuation coefficient behavior with temperature is different for the various tissues. For liver, the attenuation coefficient is nearly constant with temperature. For kidney, attenuation increases approximately linearly with temperature, while for muscle and prostate tissue, curves of attenuation vs. temperature are flat in the 25-50 degrees C range, slowly rise at medium temperatures (50-70 degrees C), and level off at higher temperatures (70-90 degrees C). Measurements were also conducted on a distilled degassed water sample and the results closely follow values from the literature.
journal_name
Ultrason Imagingjournal_title
Ultrasonic imagingauthors
Techavipoo U,Varghese T,Zagzebski JA,Stiles T,Frank Gdoi
10.1177/016173460202400404subject
Has Abstractpub_date
2002-10-01 00:00:00pages
246-60issue
4eissn
0161-7346issn
1096-0910journal_volume
24pub_type
杂志文章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::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
pub_type: 杂志文章
doi:10.1177/016173468500700202
更新日期:1985-04-01 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::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
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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::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
pub_type: 杂志文章
doi:10.1177/016173460903100303
更新日期:2009-07-01 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
pub_type: 杂志文章
doi:10.1177/016173460202400202
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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
pub_type: 杂志文章
doi:10.1177/016173469301500106
更新日期:1993-01-01 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::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::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::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::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::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::Mean frequency estimators as used in pulsed Doppler ultrasound equipment should provide an accurate (quality) and consistent (robustness) estimate over a wide range of signal conditions. In a simplified signal model, the main parameters to consider are the noise level, mean frequency, bandwidth and power of both the D...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469201400404
更新日期:1992-10-01 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
pub_type: 杂志文章
doi:10.1177/016173460302500303
更新日期:2003-07-01 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::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::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
pub_type: 杂志文章
doi:10.1177/016173469701900204
更新日期:1997-04-01 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
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469401600102
更新日期:1994-01-01 00:00:00
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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::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::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
pub_type: 杂志文章
doi:10.1177/016173468400600104
更新日期:1984-01-01 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
pub_type: 杂志文章
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更新日期:2017-05-01 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
pub_type: 杂志文章
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更新日期:2014-04-01 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::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
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更新日期:2015-01-01 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
pub_type: 杂志文章
doi:10.1177/016173468700900405
更新日期:1987-10-01 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
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更新日期:1983-01-01 00:00:00