IMPLEMENTATION, OPTIMIZATION, AND APPLICATION OF QUANTITATIVE MAGNETIZATION TRANSFER RATIO (QMTR)

Abstract

Magnetization transfer (MT) technique is an MRI technique to visualize chemical exchange between water and macromolecules in human body. However, traditional MT experiments are predominantly qualitative, while inter- and intra-subject comparisons are meaningful only if MT effect could be quantified. In this thesis, performance of the relatively new quantitative MT (qMT) technique is investigated and reviewed, followed by implementation of qMT on a clinical 3T Siemens MRI scanner. Post-processing tools are then developed to extract quantitative information from the qMT images. Healthy volunteers were scanned, establishing a table of normative qMT parameters within the healthy cohort. Later on, the minimization problem embedded within qMT is reformulated with inclusion of lower bound constraints, ensuring stability of the optimization algorithm. It is also further optimized, possibly reducing number of image acquisitions and scanning time required. All works then converge into a verified set of qMT protocol and post-processing tools for future applications.