METHOD AND SYSTEM FOR THE AMPLIFICATION OF NUCLEAR MAGNETIC RESONANCE IMAGING

摘要

A method and system to enhance MRI contrast based on nonlinear feedback fields induced by the spin of the imaged molecules are provided. It is shown that while contrast in magnetic resonance imaging (MRI) is often limited by the dependence of the magnetization on MR parameters that may not vary significantly throughout the sample, through use of the inventive system, changes in the distribution of an initially unstable magnetization configuration act back on the spins through the feedback fields to amplify contrast. Demonstrations of avalanching amplification of MRI contrast due to small differences in spin density or resonance frequency under the feedback interactions of the distant dipolar field and/or radiation damping in phantoms and in vitro human brain tissue are also provided. These demonstrations show up to 20 times improved contrast in epileptogenic lesions and malignant brain tumors, tissues with minimal contrast differences in routine MRI, which suggests that feedback-based contrast enhancement may lead to improved lesion characterization, among other potential biomedical applications.