title: Management of planum/olfactory meningiomas: predicting symptoms and postoperative complications.
abstract: OBJECTIVE
  Given their location and slow growth, olfactory groove and planum sphenoidale meningiomas often grow to large sizes before they present with clinical symptoms and pose significant surgical challenges. The goal of our study is to identify which preoperative symptoms and findings on magnetic resonance imaging are correlated with specific postoperative outcomes in order to better counsel patients preoperatively.
  
  
  METHODS
  We retrospectively identified 44 patients with planum/olfactory meningiomas treated at our institution from 1996 to 2006. We used univariate and multivariate regression models to analyze the effect of several magnetic resonance imaging characteristics (tumor volume, distance to optic chiasm, anterior cerebral artery encasement, paranasal sinus invasion, and sellar invasion) on preoperative symptoms and postoperative outcomes, including complication rate and tumor recurrence.
  
  
  RESULTS
  Only brain tumor volume (>42 cm(3)), but not distance to the optic chiasm, is independently associated with an increased likelihood of preoperative visual symptoms. Tumors with nasal sinus invasion are significantly more likely to cause postoperative surgical complications, and tumors with anterior cerebral artery encasement are associated with a greater likelihood of both postoperative complications and tumor recurrence.
  
  
  CONCLUSIONS
  We conclude that tumors larger than 3.4 cm in diameter and those whose posterior edge is within 6-8 mm of the optic chiasm should be recommended for early surgical intervention. In terms of predicting surgical complications, nasal sinus invasion and anterior cerebral artery encasement are associated with greater-risk profiles when surgery becomes necessary. Thus, it is prudent to take these specific variables into consideration when advising patients about the risks of observation and surgery for olfactory/planum meningiomas.
authors.affiliation: Department of Neurological Surgery, University of California at San Francisco, San Francisco, California, USA.
authors.forename: Corinna C
authors.initials: CC
authors.lastname: Zygourakis
authors.affiliation: Department of Neurological Surgery, University of Oklahoma, Oklahoma City, Oklahoma, USA.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Sughrue
authors.affiliation: Department of Neurological Surgery, University of California at San Francisco, San Francisco, California, USA.
authors.forename: Arnau
authors.initials: A
authors.lastname: Benet
authors.affiliation: Department of Neurological Surgery, University of California at San Francisco, San Francisco, California, USA.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Parsa
authors.affiliation: Department of Neurological Surgery, University of California at San Francisco, San Francisco, California, USA.
authors.forename: Mitchel S
authors.initials: MS
authors.lastname: Berger
authors.affiliation: Department of Neurological Surgery, University of California at San Francisco, San Francisco, California, USA. Electronic address: mcdermottm@neurosurg.ucsf.edu.
authors.forename: Michael W
authors.initials: MW
authors.lastname: McDermott
mesh_terms: D000328:Adult; D000368:Aged; D002536:Cerebral Arteries / Q000473:pathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008579:Meningioma / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D009422:Nervous System Diseases / Q000209:etiology; D019635:Neurosurgical Procedures / Q000379:methods*; D010255:Paranasal Sinus Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D011183:Postoperative Complications / Q000628:therapy*; D011237:Predictive Value of Tests; D019292:Skull Base Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome
keywords: Meningioma; Olfactory groove; Planum sphenoidale; Surgical outcome