Diffusion and diffusion tensor imaging in brain cancer.

Conventional magnetic resonance imaging provides important information on the structure of tumors, but new imaging tools are emerging that provide more detailed functional information on tumor biology. In particular, diffusion-weighted imaging (DWI) is sensitive to the tumor microenvironment so it may serve as a prognostic biomarker and an indicator of tumor response to chemoradiation. Furthermore, DWI and diffusion tensor imaging may play a role in radiation planning and assessing the long-term effects of radiation. DWI is increasingly being incorporated into clinical practice and clinical trials, but more work needs to be done to standardize acquisition techniques and analysis methods of DWI.