Intrinsic Tradeoffs in Multi-Covariate Imaging of Sub-Resolution Targets.
Journal Article (Journal Article)
Multi-covariate Imaging of Sub-resolution Targets (MIST) is an estimation-based method of imaging the statistics of diffuse scattering targets. MIST estimates the contributions of a set of covariance models to the echo data covariance matrix. Models are defined based on a spatial decomposition of the theoretical transmit intensity distribution into ON-axis and OFF-axis contributions, delineated by a user-specified spatial cutoff. We define this cutoff as the region of interest width (ROI width). In our previous work, we selected the ROI width as the first zero crossing separating the mainlobe from the sidelobe regions. This article explores the effects of varying two key parameters on MIST image quality: 1) ROI width and 2) the degree of spatial averaging of the measured echo data covariance matrix. These results demonstrate a fundamental tradeoff between resolution and speckle texture. We characterize MIST imaging performance across these tunable parameters in a number of simulated, phantom, and in vivo liver applications. We consider performance in noise, fidelity to native contrast, resolution, and speckle texture. MIST is also compared with varying levels of spatial and frequency compounding, demonstrating quantitative improvements in image quality at comparable levels of speckle reduction. In an in vivo example, optimized MIST images demonstrated 20.2% and 13.4% improvements in contrast-to-noise ratio over optimized spatial and frequency compounding images, respectively. These results present a framework for selecting MIST parameters to maximize speckle signal-to-noise ratio without an appreciable loss in resolution.
Full Text
Duke Authors
Cited Authors
- Morgan, MR; Trahey, GE; Walker, WF
Published Date
- October 2020
Published In
Volume / Issue
- 67 / 10
Start / End Page
- 1980 - 1992
PubMed ID
- 32396077
Pubmed Central ID
- PMC7565283
Electronic International Standard Serial Number (EISSN)
- 1525-8955
International Standard Serial Number (ISSN)
- 0885-3010
Digital Object Identifier (DOI)
- 10.1109/tuffc.2020.2993241
Language
- eng