Diffusion-Weighted Methods

Abstract

During the last two decades the technical advancements of Diffusion Weighted Imaging have enabled the precise and repeatable characterization of brain tumor microstructure non-invasively, mainly by the use of the apparent diffusion coefficient (ADC) as a biomarker. This has led to many applications aiding in tumor grading, prognosis assessment and treatment monitoring.Diffusion-weighted imaging (DWI) has been widely investigated for tumor imaging to localize a tumor, to estimate its borders, and to discriminate nonneoplastic masses from proliferating tumors or tumor types and grades. Further DWI was used for the separation of tumor infiltration from reversible edematous tissue changes, the detection of white matter tracts for surgical planning and postsurgical controls, the monitoring of radiation or drug therapy response of tumors, and the separation of recurrent tumor from radiation necrosis (Field and Alexander 2004). Diffusion-weighted imaging contributes pathophysiological as well as microstructural information and is therefore another piece in the puzzle of the whole picture of a brain tumor.