title: Surgical Anatomy of the Infralabyrinthine Approach.
abstract: The objective of this study is to demonstrate the surgical anatomy of the infralabyrinthine approach (ILA) and ways to prevent complications based on the complex anatomy.
  
  
  
  Cadaveric study.
  
  
  
  Ankara University Faculty of Medicine, Department of Anatomy.
  
  
  
  Temporal bones were selected from 30 sides of 20 fixed human cadaver heads. Computed tomography (CT) scans of the heads were performed and, afterward, the cadavers were dissected using a surgical microscope and electric drill.
  
  
  
  An appropriate tract could be achieved in 73.3% of the dissections by applying slight pressure to the jugular bulb (JB). The narrowest portion of the ILA was defined as the inner window, which was located superior-inferiorly between the inferior border of the cochlea and the inferior wall of the petrous apex and anterior-posteriorly between the posterior wall of the carotid canal and the cochlear opening of the cochlear aqueduct. The ILA could not be performed when the distances between the facial nerve-JB and JB-cochlea were less than 2.9 mm and 2.6 mm, respectively, on CT scan.
  
  
  
  Close attention should be paid to the access and inner window during preoperative temporal bone imaging to assess for ILA. The detailed anatomy of the route, measurements of the topography of the cochlea from the mastoid view, and angles of the route are defined to prevent complications.
authors.affiliation: Clinic of Otolaryngology, Ankara Oncology Education and Research Hospital, Ankara, Turkey Department of Anatomy, Ankara University, Faculty of Medicine, Ankara, Turkey elacomert@yahoo.com.
authors.forename: Ela
authors.initials: E
authors.lastname: Cömert
authors.affiliation: Department of Anatomy, Ankara University, Faculty of Medicine, Ankara, Turkey.
authors.forename: Ayhan
authors.initials: A
authors.lastname: Cömert
authors.affiliation: Department of Radiology, Ataturk Education and Research Hospital, Ankara, Turkey.
authors.forename: Nurdan
authors.initials: N
authors.lastname: Çay
authors.affiliation: Clinic of Otolaryngology, Ankara Oncology Education and Research Hospital, Ankara, Turkey.
authors.forename: Ümit
authors.initials: Ü
authors.lastname: Tunçel
authors.affiliation: Department of Anatomy, Ankara University, Faculty of Medicine, Ankara, Turkey.
authors.forename: İbrahim
authors.initials: İ
authors.lastname: Tekdemir
mesh_terms: D059925:Anatomic Landmarks; D002102:Cadaver; D002784:Cholesterol; D004210:Dissection; D007758:Ear, Inner / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery*; D006099:Granuloma / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D010579:Petrous Bone / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery*; D013701:Temporal Bone / Q000000981:diagnostic imaging / Q000601:surgery; D014057:Tomography, X-Ray Computed
chemical_list: D002784:Cholesterol
keywords: anatomy; cholesterol granuloma; infralabyrinthine approach; radiology; skull base surgery