Findings:
A small mass is present in the left lateral ventricle
which is isointense to gray matter on T1WI, hyperintense on T2WI, and does
not enhance. No hydrocephalus is evident.
Differential Diagnosis:
central neurocytoma (enhance), subependymoma, colloid cyst (too
high in position for colloid cyst), subependymal giant cell astrocytoma
(if other signs of TS), low grade intraventricular astrocytoma, metastasis
Discussion:
distinguishing feature: doesn't enhance, therefore other
lesions such as meningioma and choroid plexus papilloma shouldn't be included
in differential.
most common location/age: fourth vent (75%) in older
men- met primary ddx in this group.