title: Cystic optic nerve meningioma presenting with acute proptosis.
abstract: A 37-year-old woman presented with acute left-sided proptosis. Magnetic resonance imaging demonstrated a solid intraconal mass lesion with an associated 'capping' cyst. This lesion was resected and found on histological examination to be optic nerve sheath meningioma. Small perineural cysts have been reported with optic nerve sheath meningioma but we believe this to be the first reported case of a large peritumoral cyst associated with this type of mass lesion. We speculate on the aetiology of the cyst and the associated acute proptosis.
authors.affiliation: Department of Neuroradiology, Manchester Royal Infirmary, UK.
authors.forename: R D
authors.initials: RD
authors.lastname: Laitt
authors.forename: B
authors.initials: B
authors.lastname: Kumar
authors.forename: B
authors.initials: B
authors.lastname: Leatherbarrow
authors.forename: R E
authors.initials: RE
authors.lastname: Bonshek
authors.forename: A
authors.initials: A
authors.lastname: Jackson
mesh_terms: D000208:Acute Disease; D000328:Adult; D003390:Cranial Nerve Neoplasms / Q000150:complications*; D005094:Exophthalmos / Q000209:etiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008579:Meningioma / Q000150:complications*; D010146:Pain / Q000209:etiology; D014792:Visual Acuity