title: Endoscopic endonasal resection of medial orbital lesions with intraoperative MRI.
abstract: BACKGROUND
  Various approaches have been described and used for operating on lesions in the orbit. The approach selection is based on the pathology in the orbit and its exact location. This study was performed to evaluate the endoscopic endonasal approach (EEA) for orbital lesions and application of intraoperative MRI (iMRI).
  
  
  METHODS
  Since 2006, the present authors have performed 614 endoscopic endonasal procedures. iMRI was used in 409 of these cases. Three orbital lesions approached via the endonasal route with a minimum follow-up of 1 year were analysed.
  
  
  RESULTS
  EEA was used in one case of intraconal cavernoma, one extraconal cavernoma and one solitary fibrous tumour in the orbit. The lesion was located medially to the optic nerve in all cases. Radical resection was achieved and the patient's vision was improved in two cases with a preoperative visual field deficit. iMRI was useful in two cases. In one case intraoperative MRI helped to find an intraconal lesion; in the other case iMRI led to evacuation of haemostatic material and blood, which was causing compression in the orbit.
  
  
  CONCLUSIONS
  The EEA should be considered whenever a lesion in the orbit is located medially to the optic nerve. Excellent results were achieved. iMRI proved useful in selected cases.
authors.affiliation: Department of Neurosurgery, Charles University, 1st Medical Faculty, Central Military Hospital, U vojenske nemocnice 1200, 169 02, Prague, Czech Republic. david.netuka@uvn.cz
authors.forename: David
authors.initials: D
authors.lastname: Netuka
authors.forename: Václav
authors.initials: V
authors.lastname: Masopust
authors.forename: Tomáš
authors.initials: T
authors.lastname: Belšán
authors.forename: Nora
authors.initials: N
authors.lastname: Profantová
authors.forename: Vladimír
authors.initials: V
authors.lastname: Beneš
mesh_terms: D000328:Adult; D000368:Aged; D019299:Decompression, Surgical / Q000379:methods; D004724:Endoscopy / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006392:Hemangioma, Cavernous / Q000175:diagnosis / Q000601:surgery*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D053783:Magnetic Resonance Imaging, Interventional / Q000379:methods*; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000175:diagnosis / Q000601:surgery; D038361:Neuronavigation / Q000379:methods*; D009901:Optic Nerve Diseases / Q000175:diagnosis / Q000601:surgery; D009918:Orbital Neoplasms / Q000175:diagnosis / Q000601:surgery*; D011183:Postoperative Complications / Q000175:diagnosis; D054364:Solitary Fibrous Tumors / Q000175:diagnosis / Q000601:surgery*; D014792:Visual Acuity / Q000502:physiology; D014794:Visual Fields / Q000502:physiology