The importance of imaging in diagnosis of infected otogenic pneumatoceles.

Objective: Spontaneous otogenic pneumatocele is a rare entity resulting from a pressure gradient between a dehiscent temporal bone and the intracranial space. Secondary infection can ensue in patients with concurrent otomastoiditis. The current study discusses the clinical presentation and imaging characteristics of two cases of secondarily infected otogenic pneumatoceles.

Methods: Case series.

Results: Two patients were diagnosed with a temporal lobe abscess in the setting of otogenic pneumatocele. Diagnosis was aided by both CT and MRI demonstrating a diffusion restricting lesion within brain parenchyma in association with free air in close proximity to an underlying tegmen defect.

Conclusions: Prompt diagnosis of a secondarily infected otogenic pneumatocele with CT and MRI allows for surgical drainage with closure of the tegmen defect to prevent further complications and recurrence.