What is the cause of the hydrocephalus?
A rounded lesion in the region of the pineal gland. It has hyperdense material layering posteriorly and CSF density anteriorly, presumably representing blood.
An oval extraaxial, partially cystic mass with calcified rim appears to be centred in the pineal region and measures 31 x 20 mm. There is no convincing enhancement. The mass compresses the cerebral aqueduct, extends into the third ventricle with associated obstructive hydrocephalus.