Reverberation Clutter Suppression Using 2-D Spatial Coherence Analysis.

Journal Article (Journal Article)

Diffuse reverberation clutter often significantly degrades the visibility of abdominal structures. Reverberation clutter acts as a temporally stationary haze that originates from the multiple scattering within the subcutaneous layers and has a narrow spatial correlation length. We recently presented an adaptive beamforming technique, Lag-one Spatial Coherence Adaptive Normalization (LoSCAN), which can recover the contrast suppressed by incoherent noise. LoSCAN successfully suppressed reverberation clutter in numerous clinical examples. However, reverberation clutter is a 3-D phenomenon and can often exhibit a finite partial correlation between receive channels. Due to a strict noise-incoherence assumption, LoSCAN does not eliminate correlated reverberation clutter. This work presents a 2-D matrix array-based LoSCAN method and evaluates matrix-LoSCAN-based strategies to suppress partially correlated reverberation clutter. We validated the proposed matrix LoSCAN method using Field II simulations of a 64×64 symmetric 2-D array. We show that a subaperture beamforming (SAB) method tuned to the direction of noise correlation is an effective method to enhance LoSCAN's performance. We evaluated the efficacy of the proposed methods using fundamental and harmonic channel data acquired from the liver of two healthy volunteers using a 64×16 custom 2-D array. Compared to azimuthal LoSCAN, the proposed approach increased the contrast by up to 5.5 dB and the generalized contrast-to-noise ratio (gCNR) by up to 0.07. We also present analytic models to understand the impact of partially correlated reverberation clutter on LoSCAN images and explain the proposed methods' mechanism of image quality improvement.

Full Text

Duke Authors

Cited Authors

  • Ahmed, R; Bottenus, N; Long, J; Trahey, GE

Published Date

  • January 2022

Published In

Volume / Issue

  • 69 / 1

Start / End Page

  • 84 - 97

PubMed ID

  • 34437060

Pubmed Central ID

  • PMC8845080

Electronic International Standard Serial Number (EISSN)

  • 1525-8955

International Standard Serial Number (ISSN)

  • 0885-3010

Digital Object Identifier (DOI)

  • 10.1109/tuffc.2021.3108059

Language

  • eng