Table 3. Frequently performed novel imaging techniques.

Novel imaging techniques	Concept	Ref.
DWI	Measures the rate of Brownian motion of water molecules in tissue. Identification of areas of high cellularity/active tumor growth	[7–11]
DTI	As a refined form of DWI imaging, DTI helps to visualize white matter tracts. May be helpful in preoperative planning and differentiating tumor growth from pseudo-progression	[12–18]
MRI perfusion imaging	Measures tumor vascular permeability. Active tumors tend to have higher relative cerebral blood volumes	[19–21,23–26]
Magnetic resonance spectroscopy	Measures tissue metabolic activity. May be helpful in preoperative grading as well as differentiating tumor growth from pseudo-progression	[26–31]
PET imaging	Measures biochemical activity of tumor. May be helpful in preoperative grading as well as for assessment of disease progression	[32–37]

DTI: Diffusion-tensor imaging; DWI: Diffusion-weighted imaging.