Diffusion tensor imaging in cerebral tumor diagnosis and therapy.

Diffusion-weighted MR images and their analysis using the tensor model open up many new possibilities for tissue characterization, surgical planning, and treatment follow-up in patients with cerebral neoplasms. These possibilities are only just beginning to be fully explored. This article reviews the physical principles underlying diffusion tensor imaging (DTI); the various postprocessing methods available for DTI data in the context of tumor imaging; the commonly encountered patterns of tumor-related alteration to cerebral white matter, as depicted by directionally encoded color maps; and the current state of the art in DTI-based tumor diagnosis and treatment planning.