title: Splitting of the Optic Nerve by a Pituitary Macroadenoma.
abstract: BACKGROUND
  Splitting of the optic nerve by a pituitary adenoma is an extremely unusual condition with only 3 cases reported to date.
  
  
  METHODS
  A 41-year-old woman presented with visual loss as a result of an aggressive pituitary macroadenoma causing the splitting of the right optic nerve. Possible mechanisms of this condition are discussed, and the literature is reviewed.
  
  
  CONCLUSIONS
  In aneurysm and tumor cases, awareness of the exact anatomy is particularly important to preserve function. An overlooked duplication or penetration of cranial nerves may result in inadvertent injury to important structures and loss of function.
authors.affiliation: Department of Neurosurgery, Hacettepe University Faculty of Medicine, Ankara, Turkey.
authors.forename: Şahin
authors.initials: Ş
authors.lastname: Hanalioğlu
authors.affiliation: Department of Neurosurgery, Hacettepe University Faculty of Medicine, Ankara, Turkey. Electronic address: isikay@hacettepe.edu.tr.
authors.forename: İlkay
authors.initials: İ
authors.lastname: Işıkay
authors.affiliation: Department of Neurosurgery, Hacettepe University Faculty of Medicine, Ankara, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Berker
mesh_terms: D000236:Adenoma / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D000328:Adult; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D009900:Optic Nerve / Q000000981:diagnostic imaging / Q000473:pathology*; D010911:Pituitary Neoplasms / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D014786:Vision Disorders / Q000000981:diagnostic imaging / Q000209:etiology*
chemical_list: D019394:Ki-67 Antigen
keywords: Optic nerve; Pituitary macroadenoma; Splitting; Visual loss