Subependymoma - lateral ventricle

Case contributed by Yune Kwong


Incidentally detected lesion on sinus CT

Patient Data

Age: 45 years
Gender: Female

Large left lateral ventricle lesion, with internal cystic degeneration. Susceptibility images suggest calcification. A few foci of enhancement are seen, but the bulk of the lesion does not enhance. Obstruction of the foramen of Monro, with dilatation of the left lateral ventricle.


Eight fragments of white to pale tan,  rubbery  tissueranging in size from 6 x 5 x 2mm to 40 x 25 x 10mm.
Highly  fibrillary  glial  lesion  featuring  clustered  cell  bodies accompanied by microcysts, with areas of prominent Rosenthal fiber formation, thromboed  and  scleroses   blood  vessels  and  old  hemorrhage.   Perivascular pseudorosettes are present focally. Mitotic figures are not seen.  The lesion is separated from ventricular lining by a layer of white matter.  Features  qualify for subependymoma.
DIAGNOSIS: Subependymoma.

Case Discussion

At the time of imaging, the differential included meningioma, but this would be expected to show more intense and homogeneous enhancement. Central neurocytoma was also considered, as it is commonly found in the lateral ventricles near the foramen of Monro, with 'bubbly' cystic areas. However moderate to strong heterogenous enhancement would be expected.

Although subependymomas are typically described in the inferior fourth ventricle, they also occur in the lateral, third ventricles and spinal cord. They are most commonly small, although can become large as in this case. Variable enhancement is seen (typically none to mild), but marked enhancement is also a feature (more commonly in the fourth ventricle than lateral ventricles). The most common demographics is in middle-aged to elderly males. In general, the diagnosis should be considered in a hyperintense ventricular tumor with poor enhancement (other ventricular tumors enhance more prominently).

They are WHO grade I tumors.

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.