This tumor is centered on the fourth ventricle and extends out of the ventricular system via the foramen of Luschka. The main bulk of disease is extra-ventricular with extension anterior to the brainstem and into the internal acoustic meatus on the left.

Posterior fossa tumors in children consist of four main entities. As classically described, the ependymoma is the tumor that will exude from foramina in an almost plastic fashion, much akin to toothpaste being squeezed from a tube.