[Magnetic resonance tractography in neuroradiological diagnostic aspects]

Abstract

Diffusion tensor imaging is unique in its ability to non-invasively visualize white matter fiber tracts in the human brain in vivo. White matter fiber bundles of the human brain form a spatial defined by the anatomical and functional architecture. Determination of axonal pathways provides an invaluable means to study the connectivity of human brain and its functional network. Comparison of fiber tract properties across subjects requires comparison at corresponding anatomical locations. In this paper, we present application of white matter tractography method based on incoherent motion of water molecules in fiber tissue, mainly in central nervous system. This motion is itself dependent on the micro-structural environment that restricts the movement of the water molecules. In white matter fibers there is a pronounced directional dependence on diffusion. With white matter fiber tracking or tractography, projections among brain regions can be detected in the three-dimentional diffusion tensor dataset according to the directionality of the fibers. The authors indicate diagnostic possibilities of MR tractography in otolaryngology for imaging the nervous tracts of sense of hearing, smell and taste with particular consideration of otoneurological evaluation of patients with cochlear implants and bone anchored hearing aid (BAHA). White matter tracts can be evaluated independently by using diffusion tensor tractography, which appears to be a promising technique for determining changes in white matter in degenerative disease. The authors also indicate that method as a beneficial in the surgical planning for patients with intrinsic brain tumors.