Introduction: Acute hydrocephalus is a common complication of spontaneous or traumatic intracranial bleeding with extensive subarachnoid hemorrhage (SAH) or ventricular extension. However, it has never been reported to be secondary to pneumocephalus.
Patient concerns: A 32-year-old man was admitted following a motorcycle accident. Head computed tomography (CT) performed right after the accident revealed a skull base fracture and mild perimesencephalic SAH. Three days later, repeated CT revealed delayed perimesencephalic pneumocephalus and an evident enlargement of the ventricular system.
Diagnosis: The patient was diagnosed with acute obstructive hydrocephalus, which was secondary to pneumocephalus and traumatic SAH.
Interventions: The patient was treated with temporary external ventricular drainage (EVD).
Outcomes: The patient experienced an unremarkable recovery process. At follow-up 3 months later, he showed no recurrence of the hydrocephalus and the score of Glasgow Outcome Scale was 5.
Conclusion: Transient mechanical obstruction of CSF circulation and disturbance of CSF physiology might conjointly lead to the acute obstructive hydrocephalus.