Modality	Uses
CT	Localizing the tumor and defining its dimensions, morphology
MRI	Localizing the tumor and surrounding structures with a high-resolution image, diagnosis of supra- and subtentorial tumors, diagnosis of extra- and intra-axial tumors, presurgical planning with three-dimensional imaging, stereotactic biopsy, radiotherapy
DTI	Establishing spatial relationships between tumor border and white matter, assessing the progression and regression of white matter tracts caused by tumor growth or resection
fMRI	Neurosurgical planning and neurologic risk assessment by localizing the cortical regions that control language, motor, and memory functions
MRA	Understanding tumor vascularity and identifying the anatomic relationship between the tumor and blood vessels
MRS	Obtaining biochemical and metabolic information about the tumor, determining tumor type and grade by assessing the cellular contents, differentiating tumor from radiation necrosis
PET	Metabolic assessment of tumor aggressiveness (grade), assessing the highly metabolic areas within the tumor, differentiating between tumor recurrence and radiation necrosis, functional localization of cortical regions, predicting patient survival and prognosis