On head CT, some of the findings that are suggestive of subependymal giant<unk>  astrocytoma include a heterogenous mass with uniform post contrast enhancement, enlargement of the ventricles, and iso- or slightly hypoattenuating to grey matter.
Subependymal giant cell astrocytoma CT
Subependymal giant cell astrocytoma MRI
Ependymoma CT
Medulloblastoma CT
Ependymoma MRI
Oligodendroglioma MRI
Schwannoma CT
Neurofibroma CT