Delayed isolated tension intraventricular pneumocephalus after ventriculoperitoneal shunt

Abstract

Delayed and isolated tension intraventricular pneumocephalus without air in the pericerebral subarachnoid spaces is an exceptional complication of a ventriculoperitoneal (VP) shunt. We purpose an explanation for the development of such delayed pneumocephalus. A 14-year-old boy developed headaches and right-side hearing loss three months after surgical resection of a cerebellar medulloblastoma and insertion of a VP shunt. CT-scan showed isolated intraventricular pneumocephalus without air in the pericerebral subarachnoid spaces. A petrous bone defect was discovered and surgically repaired with clinical and radiographic resolution of pneumocephalus. We presume that the brain tIssue plugging the bony defect retracted following the placement of the shunt and eventually there was rupture through the pia-mater into the lateral ventricle. This could explain why isolated intraventricular occurred, as opposed to air in the subarachnoid spaces.