MR Elastography System for Breast Cancer Detection

摘要

Early diagnosis of breast cancer, which is critical for favorable clinical outcomes, is difficult because tumors and healthy tissue respond similarly to X rays and ultrasound. One physical property that clearly distinguishes healthy from cancerous tissue is mechanical stiffness or hardness. Researchers have attempted to combine external mechanical stimulation and Magnetic Resonance Imaging (MRI) to quantitatively measure the Young's modulus of tissue throughout both the breast and the prostate. This technique, Magnetic Resonance Elastography (MRE) has been called 'palpation at a distance.' One of the most challenging technical aspects of MRE is the efficient solution of the 'inverse problem,' i.e., quantitatively determining Young's modulus from MRI- measured tissue displacement data. Creare developed analytical techniques to improve the efficiency and robustness of the inverse problem solution. One technique, which utilizes an incompressible formulation of the tissue equations of motion, an adjoint method for calculating the gradient of the goodness-of-fit metric, and a quasi-Newton minimization algorithm, appears to provide a substantial improvement in efficiency over techniques used previously.