Diffusion-tensor imaging in brain tumors

Diffusion-tensor imaging (DTI) is the only novel imaging technique that is able to demonstrate white matter tracts and their structural changes related to different brain pathologies. Diffusion tensor describes the 3D diffusion phenomenon of the protons according to their microenvironmental properties allowing a unique description of the space where this molecular movement takes place. This model provides in vivo demonstration of the complex ultrastructural organization of the white matter as well as structural changes due to tumoral invasion. Current applications of DTI and magnetic resonance tractography allow accurate delineation of the eloquent white matter tracts and their relation with tumoral tissue. This article summarizes the basic physics and clinical applications of DTI in brain tumor diagnosis and follow-up. Effectiveness of different DTI metrics and magnetic resonance tractography is reviewed in tumor characterization, treatment planning and in the assessment of post-therapeutic changes. The limitations and the advancements in DTI era to minimize these limitations are also discussed. Current technical properties of DTI and future expectations of new DTI models make it a very promising tool for more precise evaluation of tumor-related structural changes in white matter tracts.