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 either of these models. Contributions from a distribution of discrete scatterer sizes for two different form factor functions (Gaussian form factors and scattering functions from Faran's theory) were calculated and linearly combined. Composite form factors created from Gaussian distributions of scatterer sizes centered at 50 µm with standard deviations of up to σ = 40 µm were fit to each scattering model between 2 and 12 MHz. Scatterer distributions were generated using one of two assumptions: the number density of the scatterer diameter distribution was Gaussian distributed, or the volume fraction of each scatterer diameter in the distribution was Gaussian distributed. Each simulated form factor was fit to a single-diameter form factor model for Gaussian and exponential form factors. The mean-squared error (MSE) between the composite simulated data and the best-fit single-diameter model was smaller with an exponential form factor model, compared with a Gaussian model, for distributions with standard deviations larger than 30% of the centroid value. In addition, exponential models were shown to have better ability to distinguish between Faran scattering model-based distributions with varying center diameters than the Gaussian form factor model. The evidence suggests that when little is known about the scattering medium, an exponential scattering model provides a better first approximation to the scattering correlation function for a broad distribution of spherically symmetric scatterers than when a Gaussian form factor model is assumed.
journal_name
Ultrason Imagingjournal_title
Ultrasonic imagingauthors
Nordberg EP,Hall TJdoi
10.1177/0161734614534399subject
Has Abstractpub_date
2015-01-01 00:00:00pages
3-21issue
1eissn
0161-7346issn
1096-0910pii
0161734614534399journal_volume
37pub_type
杂志文章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
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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
pub_type: 杂志文章
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journal_title:Ultrasonic imaging
pub_type: 杂志文章,评审
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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更新日期:2006-04-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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pub_type: 杂志文章
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更新日期:2013-04-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468500700402
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journal_title:Ultrasonic imaging
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pub_type: 杂志文章,评审
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