Wednesday, 17 October 2012

Intraventricular Cavernoma

A 30 yo female with giddiness.

Non contrast CT shows a solitary round to ovoid well circumscribed intra ventricular mass attached to left lateral ventricle. Hyper dense specks of calcification. No significant mass effect or hydrocephalus. On MRI lesion shows low signal intensity blooming on GRE, thin rim of hemosiderin on T2. Diffusion non contributory as expected. Very minimal enhancement on post contrast T1. No significant mass effect. Perilesional odema in adjacent brain parenchyma.

Imaging wise : Intraventricular cavernoma possible, all the imaging findings of a typical cavernoma may not be expected. Histopathological evaluation followed by endoscopic biopsy mentions findings favoring cavernous malformation.


Intraventricular masses represent ~ 10% of all CNS neoplasms, DDs are based on imaging findings, location, and age of the patient. Symptoms are usually non-specific and are related to mass effect and or hydrocephalus.
IVCs are rare entities. The prevalence rate of IVC varies between 2.5% to 10.8%.
44% of intraventricular cavernomas located in third ventricle, 27% in the lateral ventricle, 20% in the trigone, and 9% in the fourth ventricle.
Clinical presentation is usually non-specific often secondary to increased intracranial pressure with resultant mass effect. May have intermittent or fluctuating symptoms attributed to secondary to minor intra ventricular bleed. Hydrocephalus not present in majority of cases, depends on location.
On imaging,IVCs may show a similar appearance to that of intraparenchymal cavernoma. IVCs have been found to be more voluminous than their intra parenchymal counterparts, can measure up to several centimetres attributed to the lack of restriction from adjacent brain parenchyma allows for more unrestrictive growth.
On CT they are hyperdense well circumscribed round to ovoid masses, specks of calcification. Enhancement vary from none to avid. On MRI a well-defined mass with heterogeneous signal intensity on both T1W and T2W sequences due to areas of calcification and T1 bright methemoglobin. A hypointense peripheral hemosiderin rim on T2W images. GRE imaging is very sensitive in demonstrating the susceptibility effect of hemosiderin and in identifying the multiplicity of the lesion and therefore supporting the diagnosis of IVC.
On imaging, DDs include other intraventricular lesions including intraventricular arteriovenous malformations, low-grade astrocytomas, meningiomas, teratomas, or neurocytomas. Lack of surrounding edema on FLAIR or T2W imaging, peripheral hemosiderin, and lack of enhancement make tumor less likely and favor atypical vascular malformation. But on MRI, central hyperintensity,due to methemoglobin and peripheral hemosiderin rim, limits the differentials. Contrast enhancement does not help much in differentiation. GRE may be extremely helpful.

Intraventricular cavernoma, John D. Nguyen, MD, Sangam Kanekar, MD, and Annilyn S. Purayidom, MD applied radiology Journal Volume 39, Number 11, November 2010

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