A comparative study and analysis on techniques for diffusion-weighted magnetic resonance imaging.

Neural scientists have long been eager to find the subcortical pathways between different parts of cortex in human brain. By far, Diffusion Weighted-Magnetic Resonance Imaging (DW-MRI) is the only noninvasive technique to achieve this task in vivo. It applies a bipolar gradient to reveal diffusion of water molecules. With the assumption that the directions of neural fibers parallel to the directions in which water molecules diffuse, we can use the DW-MRI to track the neural fibers. Various signal processing techniques have been developed in extracting the directional information via DW-MRI. In this study, four techniques that are currently being used but have not been rigorously compared for performance are evaluated via custom-designed synthetic data and phantoms. By combining different techniques in accordance with their specialties, a better approach to track finer subcortical pathways in vivo can be derived and used to verify theories in human brain mapping.