title: Pneumosinus dilatans: a sign of intracranial meningioma.
abstract: BACKGROUND
  Pneumosinus dilatans affecting the sphenoid and posterior ethmoid sinuses has been reported in association with spheno-orbital meningiomas and is believed by some authors be a sign of an adjacent meningioma.
  
  
  METHODS
  We report the case of a 57-year-old man who developed progressive neurologic signs and symptoms consistent with a frontal lobe lesion. Neuroimaging studies revealed a large partially cystic mass at the base of the anterior cranial fossa that appeared to be invading the left frontal lobe and that was associated with pneumosinus dilatans of the adjacent left frontal sinus.
  
  
  RESULTS
  Although the appearance of the mass by neuroimaging was thought to be most consistent with a malignant glioma, the lesion was found at craniotomy to be a benign meningothelial meningioma.
  
  
  CONCLUSIONS
  Many previous cases of progressive optic neuropathy associated with pneumosinus dilatans affecting the sphenoid and posterior ethmoid sinuses have been found to be caused by adjacent optic nerve sheath meningiomas. This case provides further evidence that pneumosinus dilatans is a sign of intracranial meningioma.
authors.affiliation: Department of Neurosurgery, Johns Hopkins Medical Institutions, Baltimore, Maryland, USA.
authors.forename: N R
authors.initials: NR
authors.lastname: Miller
authors.forename: K C
authors.initials: KC
authors.lastname: Golnik
authors.forename: S M
authors.initials: SM
authors.lastname: Zeidman
authors.forename: R B
authors.initials: RB
authors.lastname: North
mesh_terms: D006801:Humans; D008297:Male; D008579:Meningioma / Q000150:complications / Q000175:diagnosis*; D008875:Middle Aged; D010254:Paranasal Sinus Diseases / Q000209:etiology*; D010255:Paranasal Sinus Neoplasms / Q000150:complications / Q000175:diagnosis*