Ventriculo-aerocele secondary to obstructive hydrocephalus

Delayed pneumocephalus following shunting for hydrocephalus

Delayed pneumocephalus is a rare but well-reported complication of cerebrospinal fluid diversion procedures. In most cases the air enters the intracranial cavity via a skull base defect. We report a case of hydrocephalus secondary to aqueduct stenosis. The patient developed pneumocephalus 2 months after successful placement of a ventriculoperitoneal shunt. We describe an attempt at endoscopic diagnosis and repair of the fistula. This was unsuccessful, presumably because the defect was too small to localize even with the use of intrathecal fluorescein. We subsequently performed a conventional craniotomy and anterior fossa repair with placement of an antisiphon device. We suggest that in certain cases, when patients present with long-standing hydrocephalus, it may be advisable to insert either a high-pressure valve or antisiphon device as a primary measure.

Intracranial aeroceles as a complication of frontal sinus osteoma

A case of an intracerebral aerocele as a complication of an osteoma in the frontal sinus is reported. The patient had been investigated 7 years earlier for three episodes of idiopathic nocturnal epilepsy. Roentgenograms of the skull at that time showed the presence of a small osteoma within the frontal sinus. Removal of the osteoma was undertaken via a bifrontal approach and repair to the dural defect was made with a temporalis fascia graft. Postoperatively, the patient made a good recovery but developed frequent focal left hemisphere epilepsy. It is our view that sinus osteomas that are incidentally found should be removed before complications arise.

Spontaneous infected pneumatocoele secondary to chronic otitis media

A case of spontaneous temporal pneumatocoele secondarily infected by Haemophilus parainfluenzae is reported. Its relation to the lateral ventricle and to a defect in the tegmen tympani was confirmed by computerized tomography (CT). The possible aetiological mechanisms are discussed.