title: Meningioma of the superior leaflet of the velum interpositum: A case report.
abstract: BACKGROUND
  Meningiomas of the velum interpositum in the roof of the third ventricle are rare. Knowing from which leaflet the meningioma originates and thus its relationships with the internal cerebral and Galen veins, may help in choosing the surgical approach.
  
  
  METHODS
  We report the case of a 40-year-old male with a meningioma arising from the superior leaflet of the velum interpositum. The tumor was resected successfully using the infratentorial-supracerebellar approach. Reviewing the literature, of the 22 reported cases of velum interpositum meningiomas, sufficient information regarding the precise location of the origin of the tumor was provided in 14 cases, all of which were from the inferior leaflet.
  
  
  CONCLUSIONS
  We report the first case of velum interpositum meningioma arising from the superior leaflet and give a potential explanation as to why meningiomas of the velum interpositum occur more commonly on the inferior leaflet. Distinguishing from which of the two leaflets the tumor originates may influence the surgical strategy.
authors.affiliation: Department of Neurosurgery, Notre-Dame Hospital, University of Montreal, 1560 East Sherbrooke Street, Montréal, Québec, Canada.
authors.forename: Pierre-Olivier
authors.initials: PO
authors.lastname: Champagne
authors.affiliation: Department of Neurosurgery, Notre-Dame Hospital, University of Montreal, 1560 East Sherbrooke Street, Montréal, Québec, Canada.
authors.forename: Michel W
authors.initials: MW
authors.lastname: Bojanowski
keywords: Meningioma; meningiomas without dural attachment; pineal region; velum interpositum