title: Extensive pneumocephalus extending into the lateral ventricles from a brain abscess: an intracranial complication of cholesteatoma.
abstract: 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.
  
  
  METHODS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Otolaryngology, Sakura Medical Center, Toho University, Sakura City, Chiba, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tamura
authors.affiliation: Department of Otolaryngology, Sakura Medical Center, Toho University, Sakura City, Chiba, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Department of Otolaryngology, Sakura Medical Center, Toho University, Sakura City, Chiba, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yamamoto
authors.affiliation: Department of Otolaryngology, Sakura Medical Center, Toho University, Sakura City, Chiba, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yoshida
mesh_terms: D000368:Aged; D001922:Brain Abscess / Q000150:complications* / Q000601:surgery; D002781:Cholesteatoma / Q000150:complications* / Q000601:surgery; D006801:Humans; D020547:Lateral Ventricles / Q000473:pathology*; D008297:Male; D011007:Pneumocephalus / Q000209:etiology* / Q000601:surgery; D019291:Skull Base / Q000473:pathology* / Q000601:surgery