Malignant epidermoid arising from the third ventricle: A case report

Table 1 Differential imaging considerations

Sequences	Epidermoid	Dermoid	Arachnoid cyst	Cystic lesions medulloblastoma	Cystic lesions ependymoma
T1WI	Hypointense	Hyperintense	Hypointense	Hypointense	Hypointense (Solid part)
T2WI	Iso-hyperintense	Hypo-hyperintense	Hyperintense	Heterogenous due to calcification, necrosis, and cyst formation	Foci of blooming (hemorrhage/calcification)
FLAIR	Heterogenous signal higher than CSF	Hyperintense	Hypointense	Heterogeneous signal higher than CSF	Heterogeneous signal higher than CSF
DWI	Restricted diffusion	No restriction	No restriction	Restricted diffusion	Restricted diffusion (Solid part)
Contrast	Non enhancement (in malignant transformation it enhances)	Non-enhancement	Non-enhancement	Heterogeneous enhancement	Heterogeneous enhancement
MR spectroscopy	Choline: + NAA: - Cho/Crt: +	Choline: + NAA: - Cho/Crt: +	Choline: + NAA: - Cho/Crt: +	Choline: ++ NAA: - Cho/Crt: ++ Lipid: + Lactate: +	Choline: ++ NAA: - Cho/Crt ++ Lipid: + Lactate: +
MR perfusion	-	-	-	+++ (solid part)	+++

T1WI: T1 weighted image; T2WI: T2 weighted image; FLAIR: Fluid-attenuated inversion recovery; DWI: Diffusion weighted image; NAA: N-acetylaspartate.