Objective: We report the case of a patient with extensive pneumocephalus extending into the lateral ventricles from a brain abscess arising from a cholesteatoma-induced defect in the skull base.
Case report: A 70-year-old man with cholesteatoma presented with right-sided otalgia, otorrhoea and progressive headaches. Computed tomography showed a tegmental defect (approximately 2 × 2 cm) at the right mastoid antrum. A T1-weighted, gadolinium-enhanced magnetic resonance imaging scan showed pneumocephalus in both lateral ventricles, which was directly connected to the mastoid cavity via a brain abscess and a bone defect in the skull base. Radical mastoidectomy was performed to remove the cholesteatoma. The roof of the mastoid cavity was covered extensively with fascia and a pedicled temporalis muscle flap. One week post-operatively, computed tomography and magnetic resonance imaging showed no pneumocephalus.
Conclusion: Pneumocephalus arising from a cholesteatoma-induced brain abscess and extending into the lateral ventricles is an important entity, with an atypical appearance on computed tomography and magnetic resonance imaging.