Breast tissue stiffness estimation for surgical guidance using gravity-induced excitation

Abstract

Tissue stiffness interrogation is fundamental in breast cancer diagnosis and treatment. Furthermore, biomechanical models for predicting breast deformations have been created for several breast cancer applications. Within these applications, constitutive mechanical properties must be defined and the accuracy of this estimation directly impacts the overall performance of the model. In this study, we present an image-derived computational framework to obtain quantitative, patient specific stiffness properties for application in image-guided breast cancer surgery and interventions. The method uses two MR acquisitions of the breast in different supine gravity-loaded configurations to fit mechanical properties to a biomechanical breast model. A reproducibility assessment of the method was performed in a test–retest study using healthy volunteers and was further characterized in simulation. In five human data sets, the within subject coefficient of variation ranged from 10.7% to 27% and the intraclass correlation coefficient ranged from 0.91–0.944 for assessment of fibroglandular and adipose tissue stiffness. In simulation, fibroglandular content and deformation magnitude were shown to have significant effects on the shape and convexity of the objective function defined by image similarity. These observations provide an important step forward in characterizing the use of nonrigid image registration methodologies in conjunction with biomechanical models to estimate tissue stiffness. In addition, the results suggest that stiffness estimation methods using gravity-induced excitation can reliably and feasibly be implemented in breast cancer surgery/intervention workflows.

Three‐dimensional cryogel matrix for spheroid formation and anti‐cancer drug screening

“…High swelling ratios are an evidence to the macroporous architecture of our matrices, which helps in easy nutrient flow and removal of waste required for a successful 3D cell culture. The elastic modulus of these cryogel matrices (Figure ) was found to be similar to that of breast tissue as reported in the literature (Arya et al, ; Griesenauer et al, ). In addition, these composite matrices were found to be negligibly degradable (Figure ) as compared to the control GELMA only cryogels (Figure S2), which allows them to be used for long‐term 3D cell culture required for some of the in vitro culture models.…”

Evaluation of polydimethylsiloxane‐based substrates for in vitro culture of human periodontal ligament cells

“…In addition, the elastic modulus values of PA gels have been reported in the range of 1–100 kPa (Engler et al, ; Pelham & Wang, ), which is much lower than the elastic moduli of most tissues (Abe, Hayashi, & Sato, ). For instance, surface stiffnesses for tissues range from ~17 to 22 Pa for adipose tissue (Griesenauer, Weis, Arlinghaus, Meszoely, & Miga, ; Levental, Georges, & Janmey, ), ~0.18–3.57 MPa for carotid artery (Eikendal et al, ; Hoffman et al, ), to ~0.95–16.92 MPa for cartilage (Levental et al, ; Safshekan, Tafazzoli‐Shadpour, Abdouss, & Shadmehr, ) and >1 GPa for bone (Balooch et al, ; Evans et al, ). Alternatively, polydimethylsiloxane (PDMS) provides a range of mechanical properties that are more physiologically relevant (Mata, Fleischman, & Roy, ).…”

Evaluation of the Laser-Induced Thermotherapy Treatment Effect of Breast Cancer Based on Tissue Viscoelastic Properties

“…This is similar to that of the tissues without LITT. These strain-independent properties indicate that the breast cancer tissue after LITT treatment could be modeled and measured for in vivo measurements such as MR elastography [28,40]. In fact, our results provide the first ex vivo measurements to support the linear viscoelastic assumptions of the breast cancer tissue after LITT.…”