Most common intraventricular mass in children and adults

Any age; adults > > children

Frequently bilateral

Usually incidental; rarely large enough to obstructive hydrocephalus

Lateral ventricle > > > 3rd ventricle

Cyst within or attached to choroid plexus

CE cyst wall and surrounding choroid

Hyperintense FLAIR and DWI common

± irregular peripheral calcifications

Xanthogranuloma = laden degenerative cyst; more common in adults

2° to germinal matrix hemorrhage, trauma, tumor, or vascular malformation

Intraventricular hemorrhage initially hyperechoic and hyperdense

± dependent fluid-fluid level

± clotted blood adherent to choroid plexus

May → ventriculitis &/or hydrocephalus

Post-traumatic IVH: Frequently with SAH, and usually sequelae of severe injury

Present in 15% of patients with tuberous sclerosis complex

Heterogeneously enhancing mass near foramen of Monro

± calcifications

+ intraparenchymal hamartomas

± obstructive hydrocephalus

± globe hamartomas

Enhancement alone does not allow discrimination from hamartoma

Growth suggests subependymal giant cell astrocytoma rather than hamartoma

MRS: Less than expected ↓ NAA due to neuronal elements in tumor

Synonym: Neuroepithelial cyst

Congenital, benign ependymal-lined cyst

Intraventricular, central WM of temporoparietal and frontal lobes, subarachnoid space, mesencephalon

Lateral ventricle > > > 3rd and 4th ventricle

Nonenhancing, thin-walled cyst

Round or multiseptated

Similar to CSF on all imaging

± hyperintensity on T2WI and FLAIR

Lateral > 3rd and 4th ventricle in children

4th ventricle most common site in adults

Usually < 1 year of age at diagnosis

Males > > > females

Rarely bilateral

Usually present with hydrocephalus secondary to obstruction, CSF overproduction by tumor or hemorrhage impaired CSF resorption

Differentiation from choroid plexus carcinoma is histologic, not radiologic

CT: Lobulated, isodense, or hyperdense

± punctate foci calcification

T2 hypointense center

Intense contrast enhancement

MRS: Absent NAA and Cr/PhCr peak, increased lactate secondary to necrosis, not necessarily more aggressive

± CSF metastases

≈ always in lateral ventricle

Usually 3-5 years of age

Males = females

Usually present with hydrocephalus ± focal neurological deficits related to local brain invasion

Heterogeneous mass with irregular margins + parenchymal invasion ± surrounding edema

Cysts, hemorrhage, and necrosis common

MRS: Absent NAA and Cr/PhCr peak; higher choline peak than papilloma + increased lactate

± CSF metastasis

Lateral ventricle atrium most common site; left > right

Uncommon in children; consider NF2

Pediatric meningiomas: More frequently large, cystic, rapidly growing, and malignant vs. adult disease

Lobular, intensely enhancing intraventricular mass

± calcification ± cysts, hemorrhage

Heterogeneity or indistinct margins favor higher degrees of malignancy