Intraventricular Pneumocephalus as a Complication of Ventriculoperitoneal Shunt.

Pneumocephalus is defined as the presence of air in the intracranial cavity, and this complication is rare after ventriculoperitoneal shunt (VPS) surgery. It can be caused by traumatic brain injury (TBI), surgical interventions, and anatomical or spontaneous malformation. We present a case of intraventricular pneumocephalus associated with the placement of a VPS. The patient was a 40-year-old man who had a VPS inserted 10-years ago due to hydrocephalus caused by TBI. He presented to the emergency room with complaints of headache, vomiting, rhinoliquorrhea, and fever. Computed tomography of the skull showed ventricular dilatation with intraventricular pneumocephalus. In a three-dimensional reconstruction, a bone defect was visualized with meningocele at the base of the skull that would explain the cerebrospinal fluid fistula. The meningocele was surgically corrected. After 14 days of antibiotic treatment, a new VPS was placed and the patient progressed satisfactorily. Pneumocephalus associated with VPS is a rare condition that can develop secondary to a combination of the shunt effect and an anatomical defect at the base of the skull. Excessively negative and persistent intracranial pressure of the shunt allows air to enter and fill the existing vacuum through the defect in the skull base. This bone defect may be congenital, due to traumatic brain injury, or a result of hydrocephalus itself. Computed tomography of the skull is an excellent investigation for the visualization of bone defects, and treatment involves a correction of the fistula. Pneumocephalus associated with VPS is rare. The presence of rhinoliquorrhea is a strong indication of the condition. Once the presence of a fistula is confirmed, it should be corrected to prevent worsening of the pneumocephalus.