Table 2.

Most common differential diagnosis along with their characteristic features as an exclusion criteria.

	Characteristic features
	T1	T2/T2 FLAIR (Fluid attenuated inversion recovery)	DWI	Post contrast
Epidermoid cyst	Isointense to CSF	Heterogeneous signal from isointense to intensity higher than CSF	Restriction on DWI: hyperintense, similar ADC (Apparent diffusion coefficient) values compared to adjacent brain parenchyma	Peripheral enhancement
Lymphangioma	Isointense to brain parenchyma	Hyper intense with occasional multiple fluid: fluid levels and internal septations	Focal areas of restricted diffusion	Marginal and septal enhancement and a variable solid component enhancement
Meningioma	Isointense to hypointense compared to the optic nerve	Mildly hyperintense compared to the optic nerve	Restriction and ADC value vary according to the histological form	Homogeneous enhancement
Glioma	Hypointense heterogeneous with cystic and solid components.	hyperintense centrally with a thin low-signal at the periphery representing the dura.	Variable intensity and ADC values	Variable enhancement
Tuberculoma	Isointense to grey matter ± central hyperintensity representing caseation.	Isointense to grey matter ± a central hypointensity representing gliosis and abundant monocytes infiltration, surrounded by hyperintense T2/T2 FLAIR vasogenic edema.	Central low signal but if liquid necrosis is present centrally, may be high signal.	Usually appears as ring-enhancement.
Hematoma	Intermediate signal at hyperacute period.	Hyperintense at hyperacute period. Hypointense at chronic period.	Might be bright at hyperacute period.	Peripheral enhancement around the non-enhancing clot may be visible.
Orbital varix	Hypointense	Hypointense	None	Matches other veinous structures.

DWI: diffusion-weighted imaging; CSF: cerebro-spinal fluid.