title: Unilateral Tailored Fronto-Orbital Approach for Giant Olfactory Groove Meningiomas: Technical Nuances.
abstract: OBJECTIVE
  Giant olfactory groove meningiomas (maximum diameter ≥6 cm) remain a surgical challenge. Historically, extensive anterior and antero-lateral approaches have been the primary approaches for removal of such large tumors with limitations and morbidity pertaining to each approach. Herein, the authors describe a minimally invasive, unilateral, tailored fronto-orbital approach for resection of these complex lesions with an emphasis on preservation of the anterior cerebral arteries and olfactory nerves.
  
  
  METHODS
  A 4-stage approach using neuronavigation is performed: 1) predefined corridor, 2) identification of the ipsilateral anterior cerebral artery, 3) postdefined corridor, and 4) tumor base. The details of this approach are described below in a stepwise fashion and supplemented by a sample of 3 cases utilizing this technique.
  
  
  RESULTS
  In the 3 representative cases in which this technique was used, gross total resection was achieved without injury to any of the adjacent neurovascular structures. Significant sellar extension can be resected through a second stage endoscopic endonasal approach.
  
  
  CONCLUSIONS
  Giant olfactory groove meningiomas (≥6 cm) can be safely and completely resected with this 4-stage, unilateral fronto-orbital technique. Furthermore, early identification and preservation of the adjacent critical neurovascular structures can be achieved. This technique avoids the inherent limitations and morbidity associated with the more classic pterional and bifrontal approaches respectively while minimizing normal tissue disruption.
authors.affiliation: Department of Neurosurgery, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA.
authors.forename: Angela E
authors.initials: AE
authors.lastname: Downes
authors.affiliation: Department of Neurosurgery, University of Colorado School of Medicine, Aurora, Colorado, USA.
authors.forename: Jacob L
authors.initials: JL
authors.lastname: Freeman
authors.affiliation: Department of Neurosurgery, University of Colorado School of Medicine, Aurora, Colorado, USA.
authors.forename: D Ryan
authors.initials: DR
authors.lastname: Ormond
authors.affiliation: Department of Neurosurgery, University of Colorado School of Medicine, Aurora, Colorado, USA.
authors.forename: Kevin O
authors.initials: KO
authors.lastname: Lillehei
authors.affiliation: Department of Neurosurgery, University of Colorado School of Medicine, Aurora, Colorado, USA. Electronic address: samy.youssef@ucdenver.edu.
authors.forename: A Samy
authors.initials: AS
authors.lastname: Youssef
mesh_terms: D000368:Aged; D002536:Cerebral Arteries / Q000601:surgery; D003072:Cognition Disorders / Q000209:etiology; D003399:Craniotomy; D005260:Female; D005624:Frontal Bone / Q000601:surgery*; D020233:Gait Disorders, Neurologic / Q000209:etiology; D006801:Humans; D008297:Male; D008579:Meningioma / Q000150:complications / Q000523:psychology / Q000601:surgery*; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D009296:Nasal Cavity / Q000601:surgery; D019635:Neurosurgical Procedures / Q000379:methods*; D009832:Olfactory Nerve / Q000601:surgery; D009833:Olfactory Pathways / Q000473:pathology / Q000601:surgery*; D009915:Orbit / Q000601:surgery*; D010554:Personality Disorders / Q000209:etiology; D020127:Recovery of Function
keywords: Anterior cerebral artery; Fronto-orbital craniotomy; Keyhole concept; Olfactory groove meningioma; Olfactory nerve; Optic nerve