This document discusses various types of intraventricular tumors and other lesions. It describes tumors that originate from the ventricular walls, septum pellucidum, and choroid plexus, including ependymoma, subependymoma, central neurocytoma, subependymal giant cell astrocytoma, choroid plexus papilloma, choroid plexus carcinoma, and meningioma. It also discusses other intraventricular lesions like metastasis, colloid cysts, neurocysticercosis, hydatid cyst, and tuberculoma. Specific examples are provided with images of subependymoma, central neurocytoma, subependymal giant cell astro

1. Intraventricular Tumour.
Dr: ABD ALLAH NAZEER. MD.

2. 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.

3. Neoplasms of the ventri-cular wall
and septum pellucidum.
ependymoma
subependymoma
central neurocytoma
subependymal giant cell astrocytoma
Neoplasms of the choroid plexus
choroid plexus papilloma
choroid plexus carcinoma

4. Others
intraventricular meningioma
intraventricular metastasis
oligodendroglioma
pilocytic astrocytoma
glioblastoma multiforme
intraventricular CNS lymphoma
medulloblastoma
primitive neuroectodermal tumour
sarcoma
intraventricular teratoma
Non-neoplastic lesions
colloid cysts
neurocysticercosis
intracranial hydatid cyst
intracranial tuberculoma

9. 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 .

10. Sites:
fourth ventricle: 50-60%, lateral ventricles: 30-40%, third ventricle: rare
central canal of the spinal cord: rare
They are usually small, typically less than 2cm in size 6.
CT
Isodense 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 matter
usually homogenous but may be heterogenous in larger lesions
T2 WI: hyper intense to adjacent white and grey matter
again, heterogeneity my be seen in larger lesions, with suceptibility
related signal drop out due to calcifications occasionally seen
no adjacent parenchymal oedema (as no brain invasion is present) 6
T1 C+ (Gd)
usually no enhancement, although at times may demonstrate mild
enhancement

11. Subependymoma of 4th ventricle

12. Subependymoma of the right lateral ventricle

13. 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

15. Central neurocytoma

16. Subependymal Giant Cell Astrocytoma
Overview
Subependymal 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

17. SEGA

18. SEGA

22. Choroid plexus carcinoma

23. Choroid plexus carcinoma

24. 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

25. Intraventricular meningioma

26. Intraventricular meningioma

27. Intra-ventricular metastasis

31. Intra-ventricular lymphoma

32. 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 hyperdense
isodense and hypodense cysts are uncommon
calcification is uncommon 2
MRI: MR signal characteristics include
T1 - typically high T1 signal (short T1) - can be variable
T1 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

33. Colloid cysts

34. Colloid cysts

35. 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.

36. Intra-cerebral neurocysticercosis

37. Intra-ventricular neurocysticercosis

38. Intra-ventricular neurocysticercosis

39. 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 .

40. Hydatid cyst within the
right lateral ventricle