title: Lack of Evidence for Nonotosclerotic Stapes Fixation in Human Temporal Bone Histopathology.
abstract: OBJECTIVE
  Nonotosclerotic stapes fixation does not represent a significant cause of stapes ankylosis in patients undergoing stapedectomy; the vast majority have otosclerosis.
  
  
  BACKGROUND
  Nonotosclerotic stapes fixation has been proposed as the diagnosis in 30 to 40% of patients undergoing stapedectomy (after excluding rare congenital, systemic, and syndromic causes of stapes fixation and tympanosclerosis). This finding was based on the histopathologic evaluation of total stapedectomy surgical specimens. Since these specimens do not include the surrounding otic capsule, the histopathologic evidence of otosclerosis may be missed.
  
  
  METHODS
  Human temporal bone specimens from patients who underwent stapes mobilization, stapedotomy, or stapedectomy during life were evaluated for histologic evidence of otosclerosis. Patients with a history of temporal bone trauma, tympanosclerosis, and congenital, systemic, or syndromic causes of stapes fixation were excluded. Therefore, most temporal bone donors carried a clinical diagnosis of otosclerosis.
  
  
  RESULTS
  Two hundred ten specimens from three temporal bone collections were independently evaluated. Otosclerosis was found on histology in 99% (207/210). Therefore, the incidence of nonotosclerotic stapes fixation was 1% (3/210). In two of the three patients who did not have otosclerosis, the contralateral temporal bone had otosclerosis on histopathologic evaluation. These patients may have had otosclerosis in the footplate only (which was removed at the time of surgery and not available for review).
  
  
  CONCLUSIONS
  Nonotosclerotic stapes fixation is not likely a distinct pathologic classification from otosclerosis. Most patients diagnosed with nonotosclerotic stapes fixation likely have otosclerosis, but do not have otosclerotic foci in the stapes itself.
authors.affiliation: *Department of Otology and Laryngology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts †Department of Otolaryngology, University of Minnesota, Minneapolis, Minnesota ‡Neurotology and House Histological Temporal Bone Laboratory, David Geffin School of Medicine at UCLA, Los Angeles, California.
authors.forename: Alicia M
authors.initials: AM
authors.lastname: Quesnel
authors.forename: Reuven
authors.initials: R
authors.lastname: Ishai
authors.forename: Sebahattin
authors.initials: S
authors.lastname: Cureoglu
authors.forename: Fred
authors.initials: F
authors.lastname: Linthicum
authors.forename: Ivan A
authors.initials: IA
authors.lastname: Lopez
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Nadol
authors.forename: Michael J
authors.initials: MJ
authors.lastname: McKenna
mesh_terms: D006801:Humans; D010040:Otosclerosis / Q000473:pathology* / Q000601:surgery; D013199:Stapes / Q000473:pathology*; D013200:Stapes Mobilization; D013201:Stapes Surgery; D013701:Temporal Bone / Q000473:pathology* / Q000601:surgery