Bilateral Sequential Spontaneous Otogenic Pneumocephalus: Lessons in Pathophysiology and Management

Background: Spontaneous intradural pneumocephalus is an extremely rare but serious condition related to defects in the temporal bone and dura. The precise mechanism by which this otogenic complication occurs is poorly understood.

Objective: Report the details of an unusual case of initially unilateral spontaneous otogenic pneumocephalus followed by contralateral pneumocephalus which presented after surgical repair of temporal bone and dural defects on the initial side.

Case: A 73-year-old obese male presented with bilateral retroorbital pain and headache; he was found to have unilateral intradural pneumocephalus in the temporal lobe with an adjacent defect in the temporal bone. He underwent surgical repair of the initial defect in the temporal bone and dura via a middle cranial fossa approach with obliteration of the mastoid cavity. His symptoms and degree pneumocephalus on this side decreased initially after surgery. Two weeks after surgery, he developed worsening pneumocephalus on the contralateral side in the left temporal and frontal lobes with weakness and somnolence. This side was repaired via a similar technique without mastoid obliteration. Two weeks after surgery the patient recovered to a normal level of consciousness.

Conclusion: Spontaneous otogenic intradural pneumocephalus is an extremely rare but serious condition; unfortunately, the pathophysiology is incompletely understood. This unusual case, in which repair of the initial defect may have predisposed to development of pneumocephalus via a defect in the skull base on the contralateral side, offers insight to the complex underlying pathophysiology.