Tension Pneumoventricle Secondary to Cutaneous-Ventricular Fistula: Case Report and Literature Review

Tension pneumoventricle (TPV) is a subtype of tension pneumocephalus in which the air is trapped inside the ventricles through a one-way osteodural defect, causing an increase in intracranial pressure. TPV secondary to cutaneous-ventricular fistula has been reported only twice in the literature. Herein, we report the third case in a 53-year-old woman who developed TPV with decreased level of consciousness after removal of a posterior fossa meningioma while she was on external ventricular drainage. There was no identifiable bony defect on neuroimaging. The drain was changed urgently, and the fistula located at the drain tunneling site was sealed. This case report highlights the importance of suspecting and treating cutaneous-ventricular fistulas in TPV urgently in patients without skull base defects or those who showed no improvements with external ventricular drainage.