Intraventricular Tumour.

Dr: ABD ALLAH NAZEER. MD.

Intraventricular neoplasms are rare and arise from periventricular structures such as the walls of the ventricular system, the septum pellucidum and the choroid plexus. Many tumour types arise from, or can bulge into the ventricular system, although there are certain lesions that are relatively restricted to ventricles.

Neoplasms of the ventri cular wall and septum pellucidum.ependymomasubependymomacentral neurocytomasubependymal giant cell astrocytomaNeoplasms of the choroid plexuschoroid plexus papillomachoroid plexus carcinoma

Othersintraventricular meningiomaintraventricular metastasis oligodendrogliomapilocytic astrocytomaglioblastoma multiforme intraventricular CNS lymphomamedulloblastomaprimitive neuroectodermal tumoursarcomaintraventricular teratomaNon-neoplastic lesions colloid cystsneurocysticercosisintracranial hydatid cystintracranial tuberculoma

Subependymomas are uncommon, benign (WHO grade I) tumours which are slow growing and non-invasive.These tumours were previously also known as subependymal astrocytomas, not to be confused with subependymal giant cell astrocytomas seen with tuberous sclerosis. They are also considered by some to be variants of ependymomas, with which they may co-exist .

Sites:fourth ventricle: 50-60%, lateral ventricles: 30-40%, third ventricle: rarecentral canal of the spinal cord: rareThey are usually small, typically less than 2cm in size 6.CTIsodense to somewhat hypodense intraventricular mass compared to adjacent brain, which does not usually enhance. If large, it may have cystic or even calcific (up to half of cases 3) components. Surrounding vasogenic oedema is usually absent.MRI: T1WI.

iso - hypointense to white matterusually homogenous but may be heterogenous in larger lesions

T2 WI: hyper intense to adjacent white and grey matteragain, heterogeneity my be seen in larger lesions, with suceptibility related signal drop out due to calcifications occasionally seenno adjacent parenchymal oedema (as no brain invasion is present) 6

T1 C+ (Gd) usually no enhancement, although at times may demonstrate mild enhancement

Subependymoma of 4th ventricle

Subependymoma of the right lateral ventricle

The central neurocytoma: is rare intra-ventricular tumour that is typically attached to the septum pellucidum.The vast majority of central neurocytomas are located entirely within the ventricles. Typical locations include.lateral ventricles around foramen of Monro (most common): 50%Both lateral and 3rd ventricles: 15%Bilateral: 15%3rd ventricle in isolation: 5%

CT Scan, Usually hyperdense and punctate calcification seen in 50%.MRI: T1

iso intense to grey matter heterogenous

T1 C+ mild-moderate heterogeneous enhancement

T2 / FLAIR typically iso to somewhat hyper intense compared to brain

Central neurocytoma

Subependymal Giant Cell Astrocytoma OverviewSubependymal giant cell astrocytoma (SEGA) is a tumor that arises in the ventricular system of people with tuberous sclerosis, a rare genetic disease that causes benign tumor growth throughout the body.Because these tumors are found in the ventricles, the fluid-filled spaces within the brain, they can obstruct spinal fluid flow and cause neurologic symptoms

SEGA

SEGA

Choroid plexus carcinoma

Choroid plexus carcinoma

Intraventricular meningiomas are rare intracranial tumours that represent an uncommon subtype of the more-classical extra-axial meningioma and represent between 0.5 and 2% of all meningiomas. Despite its rarity, they represent one of the commonest adult intraventricular neoplasms 4.

80% trigone of lateral ventricle 15% third ventricle 5% fourth ventricle

Intraventricular meningioma

Intraventricular meningioma

Intra-ventricular metastasis

Intra-ventricular lymphoma

A colloid cyst of the third ventricle is a benign epithelial lined cyst with characteristic imaging features. Although usually asymptomatic, they can present with acute and profound hydrocephalus

CT: Typically seen as a well defined, rounded lesion at the roof of the 3rd ventilcle unilocular typically hyperdenseisodense and hypodense cysts are uncommoncalcification is uncommon 2 MRI: MR signal characteristics includeT1 - typically high T1 signal (short T1) - can be variableT1 C+ (Gd) - only rarely demonstrates thin rim enhancement, but usually this represents enhancement of the adjacent and stretched septal veins 3 T2 - typically low T2/T2* signal (short T2) - can be variable

Colloid cysts

Colloid cysts

Cysticercosis is currently considered the most common parasitic disease of the CNS. In about 10% of neurocysticercosis cases, the cysts are found within the cerebral ventricles or in cisterns. The lesions are usually clinically silent until obstruction occurs, secondary to either the location of the cystic lesion or associated ependymitis caused by adjacent granulomatous response. The most common symptoms are related to hydrocephalus. The onset of symptoms, including headache, vomiting, seizures, can be rather sudden and can result in death. A degenerating cyst can cause symptoms of meningitis.

Intra-cerebral neurocysticercosis

Intra-ventricular neurocysticercosis

Intra-ventricular neurocysticercosis

Hydatid disease is caused by the Echinococcus granulosus of the canine tapeworm. The normal cycle is: dog as worm carrier and definitive host and sheep as echinococcus carrier and intermediate host. Man is an accidental echinococcus carrier .

Hydatid cyst within the right lateral ventricle