Table 3. Different neuroimaging techniques implemented for glioma^4,45,46.

Neuroimaging techniques	Condition	Observation
CT Scan	Glioma Subependymal nodules (periventricular region) Subependymal astrocytoma Oligodendroglioma	Increased tissue cellularity, heterogeneous Less than 6 in number; Calcified nodules Isodense nodules obstructing the foramen of Monro, resulting ventricular dilatation Well defined tumor calcification
Non-contrast CT Scan	Subependymal astrocytoma	Calcification and small cysts
MRI	Glioma Ependymoma	Ill defined margins, surrounding edema, hemorrhage, necrosis Rise in choline levels, reduced N-acetyl aspartate Heterogeneous, cysts, calcification, occasional hemorrhage
• T1-weighted image	Glioma Subependymal astrocytoma	Hypointense to isointense, pattern with heterogeneous enhancement on contrast infusion, ring enhancement is sometimes seen but less common Isointense with cerebral cortex Isointense with the white matter
• T2-weighted image	Glioma Subependymal astrocytoma	Hyperintense Isointense with cerebral cortex Isointense with the white matter Homogeneous or heterogeneous enhancement
1H MRS	Parenchymal lesions Glioma	Multiple parenchymal lesions showing increased signal intensity Increasing choline/creatine/lactate and decreasing N-acetylaspartate correlate with tumor progression, helpful in cases of recurring tumor
Echo Planar MRI		Mapping of tumor blood flow and extends better resolution of tumor versus surrounding edema at tumor border
SPECT Thallium 201	Glioma	Distinguishes benign from malignant lesions Amount of thalium uptake correlates with grade of tumor
1MT SPET	Glioma	Employs Iodine-123α methyl L-tyrosine for detecting tumors recurrence
18F-FDG PET	Glioma	Differentiate between recurrent or residual tumor and radiation necrosis
18F-Fluoromisonidazole PET		Physiologic marker for tumor progression and radioresistance
Amino acid and amino acid analog PET tracers		Amino acid uptake is mediated by type L amino acid carriers, upregulated in tumor vasculature
18F-FLT	Glioma	Biomarker for differentiating between radiation necrosis and tumor recurrence. Marker for tumor proliferation