title: Study of the improvement in bone conduction threshold after stapedectomy.
abstract: OBJECTIVE
  Bone conduction threshold depression is not always a result of inner ear and cochlear nerve pathology. In fact, middle ear pathologies may be responsible for such threshold depression, as occurs in otosclerosis. The aims of this study were to evaluate the improvement of bone conduction threshold in patients with otosclerosis that underwent stapedectomy and to study the postoperative audiological results.
  
  
  METHODS
  This was a retrospective study on 95 patients (116 ears) diagnosed with otosclerosis having conductive or mixed hearing loss that received surgery (stapedectomy and complete removal of the footplate) consecutively. Audiometry was performed on all patients pre- and postoperatively (one month and one year after surgery). Bone and air conduction thresholds were measured at 4 frequencies (500, 1000, 2000 and 4000Hz).
  
  
  RESULTS
  The air-bone gap was closed, with a residual air-bone gap below 10dB in 92.2% of the patients and below 5dB in 79.3% of the cases. The air conduction threshold improved an average of 25dB. The patients that had an affected bone conduction threshold preoperatively improved bone conduction postoperatively at the frequencies of 1000 and 2000Hz (6 and 12dB, respectively). Consequently, the Carhart notch disappeared on the audiogram. These results were maintained at one year of follow up.
  
  
  CONCLUSIONS
  We found a significant improvement in the bone conduction threshold at the frequencies of 1000 and 2000Hz and a disappearance of the Carhart notch in the audiogram after stapedectomy and total footplate removal in patients diagnosed with otosclerosis having mixed hearing loss.
authors.affiliation: Servicio de Otorrinolaringología, Hospital Universitario Donostia, San Sebastián, España. Electronic address: leire.garcia.iza@gmail.com.
authors.forename: Leire
authors.initials: L
authors.lastname: García-Iza
authors.affiliation: Servicio de Otorrinolaringología, Hospital Universitario Donostia, San Sebastián, España.
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Navarro
authors.affiliation: Servicio de Otorrinolaringología, Hospital Universitario Donostia, San Sebastián, España.
authors.forename: Miren
authors.initials: M
authors.lastname: Goiburu
authors.affiliation: Servicio de Otorrinolaringología, Hospital Universitario Donostia, San Sebastián, España.
authors.forename: Nuria
authors.initials: N
authors.lastname: Pérez
authors.affiliation: Servicio de Otorrinolaringología, Hospital Universitario Donostia, San Sebastián, España.
authors.forename: Xabier
authors.initials: X
authors.lastname: Altuna
mesh_terms: D000388:Air; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold / Q000502:physiology*; D001844:Bone Conduction / Q000502:physiology*; D001842:Bone and Bones; D005260:Female; D006314:Hearing Loss, Conductive / Q000209:etiology / Q000601:surgery; D046089:Hearing Loss, Mixed Conductive-Sensorineural / Q000209:etiology / Q000601:surgery; D006801:Humans; D008297:Male; D010040:Otosclerosis / Q000150:complications / Q000601:surgery*; D011184:Postoperative Period; D012189:Retrospective Studies; D013201:Stapes Surgery; D016896:Treatment Outcome
keywords: Audiometry; Audiometría; Bone conduction; Estapedectomía; Otosclerosis; Stapedectomy; Vía ósea