Performance analysis of steady-state harmonic elastography.

Phys Med Biol

Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA.

Published: May 2007

AI Article Synopsis

  • Shear modulus estimation can be complicated by the challenges of the inverse elasticity problem, affecting both statistical accuracy and image quality.
  • Experiments on simulated and gelatin phantoms revealed that the spatial resolution of magnetic resonance elastography (MRE) depends on regularization and spatial filtering methods.
  • Increased regularization and spatial filtering were found to enhance the elastographic contrast-to-noise ratio (CNR) and improve the statistical accuracy of the shear modulus estimation, while subdomain size and overlap did not significantly impact results.

Article Abstract

Shear modulus estimation can be confounded by the ill-posed nature of the inverse elasticity problem. In this paper, we report the results of experiments conducted on simulated and gelatin phantoms to investigate the effect of various parameters (i.e., regularization, spatial filtering and the subzone generation process) associated with shear modulus reconstruction on the statistical accuracy (mean squared error), and image quality (i.e., contrast and spatial resolution) of the recovered mechanical properties. The results indicate several interesting observations. Firstly, the intrinsic spatial resolution of magnetic resonance elastography (MRE) is dependent on both regularization and spatial filtering. Secondly, the elastographic contrast-to-noise ratio (CNR(e)) increases with increasing regularization and spatial filtering, but it was not affected by the zoning parameters (i.e., the subzones and the extent of the overlap). Thirdly, the statistical accuracy (MSE) of the recovered property improved with increasing regularization, and spatial filtering weight, but the size of the subdomains and their overlap had no significant effect.

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http://dx.doi.org/10.1088/0031-9155/52/10/002DOI Listing

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