A constrained modulus reconstruction technique for breast cancer assessment

Abstract

A reconstruction technique for breast tissue elasticity modulus is described. This technique assumes that the geometry of normal and suspicious tissues is available from a contrast-enhanced magnetic resonance image. Furthermore, it is assumed that the modulus is constant throughout each tissue volume. The technique, which uses quasi-static strain data, is iterative where each iteration involves modulus updating followed by stress calculation. Breast mechanical stimulation is assumed to be done by two compressional rigid plates. As a result, stress is calculated using the finite element method based on the well-controlled boundary conditions of the compression plates. Using the calculated stress and the measured strain, modulus updating is done element-by-element based on Hooke's law. Breast tissue modulus reconstruction using simulated data and phantom modulus reconstruction using experimental data indicate that the technique is robust.

Quantitative sparse array vascular elastography: the impact of tissue attenuation and modulus contrast on performance

“…25,26 However, in vascular imaging, additional constraints (i.e., geometric) are required to produce stable modulus elastograms. [32][33][34][35] Geometrically constrained inversion methods can tolerate higher noticeable amounts of measurement noise than those with just smoothness constraints. 33,35 We performed a pair-wise Welch's t-test on the results reported in Fig.…”

“…(2) may not provide unique modulus elastograms 30 because the inverse elasticity problem is ill-posed; however, including geometric information in the modulus recovery process will transform the ill-posed problem to a well-posed one. [31][32][33][34][35] We included geometric information in the image reconstruction process by minimizing the following objective function:…”

Elasto‐mammography: Theory, Algorithm, and Phantom Study

“…There have been elastography studies based on either ultrasound or MRI breast imaging [6][7][8][9][10][11][12]. Ophir et al [6,7] and Souchon et al [8] proposed an ultrasound elastography modality for quantitative imaging of the elastic modulus distributions in biological tissues.…”

“…Muthupillai et al [9] and Manduca et al [10] developed an algorithm to reconstruct the shear modulus distribution using acoustic strain wave propagation measured with MRI technique. Plewes et al [11] and Samani et al [12] provided a finite-element iteration method to reconstruct the distribution of elastic moduli in a breast containing suspicious tumors, based on the MRI deformation measurement under compression loading.…”

Detecting Mechanical Abnormalities in Prostate Tissue Using FE-Based Image Registration

“…In this paper, we describe an image registration based elastography technique for recovering the Young's modulus of a visually suspicious region in a 3D TRUS volume of the prostate. Similar to elastography techniques of Samani et al [6] and Boctor et al [7] it is assumed that the Young's modulus of each tissue type is constant throughout its volume. This assumption provides anatomical constraints which impose a discrete Young's modulus distribution in the reconstruction.…”