Abstract: | A case of spontaneous nontraumatic cerebrospinal fluid rhinorrhoea secondary to aqueductal stenosis is reported. The patient required direct repair of the fistula after the insertion of a ventriculoperitoneal shunt for aqueductal stenosis. We emphasise an unusual complication of tension pneumocephalus in a case where the shunt patency had been substantiated. Intracranial pressure fall due to the siphon effect in the ventriculoperitoneal shunt tubing in the erect position might be responsible for ingress of an excessive amount of air. |