Axial CT without contrast of the brain (above left) shows a small, round, faintly dense lesion in the midline near the Foramen of Monro in the third ventricle while the axial CT more superiorly (above right) shows dilation of the lateral ventricles with transependymal flow of cerebrospinal fluid with the right lateral ventricle herniated to the left. There are additional signs of increased intracranial pressure, evidenced by the effacement of the basilar cisterns and sulci. Coronal CT (below left) shows the faintly dense round lesion in the third ventricle which is much better seen on the coronal CT obtained after placement of a ventriculoperitoneal shunt (below right).
