title: Transmastoid approach to the superior semicircular canal: An anatomical study.
abstract: OBJECTIVE
  We examined the anatomic features of the top of the superior semicircular canal (SSC) to help guide the surgeon considering resurfacing or plugging of an associated dehiscence, thorough the transmastoid (TM) approach.
  
  
  METHODS
  19 selected cadaveric temporal bones, which had no supralabyrinthine tract, were dissected, and distances between the SSC and various structures within the temporal bone were measured with a, fine caliper.
  
  
  RESULTS
  The average distances from the sino-dural angle, horizontal canal top, and subacurate artery, to the top of the SSC were 31.1, 7.8, and 3.9 mm, within a small range. 7 (36.8%) out of 19 bones with a, low hanging tegmen needed a wide exposure and elevation of the dura to access the SSC top.
  
  
  CONCLUSIONS
  Knowledge of the anatomical details associated with the SSC from this study may help to, access the SCC dehiscence safely for resurfacing surgery via a TM approach.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Nara Medical University School of Medicine, Nara, Japan. Electronic address: toshya@naramed-u.ac.jp.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Yamanaka
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
authors.forename: G Mark
authors.initials: GM
authors.lastname: Pyle
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Nara Medical University School of Medicine, Nara, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hosoi
mesh_terms: D002102:Cadaver; D006801:Humans; D008416:Mastoid / Q000033:anatomy & histology*; D012665:Semicircular Canals / Q000033:anatomy & histology*; D013701:Temporal Bone / Q000033:anatomy & histology
keywords: Anatomical study; Dizziness; Superior semicircular canal dehiscence; Transmastoid approach