title: Ear surgery techniques results on hearing threshold improvement.
abstract: BACKGROUND
  Bone conduction (BC) threshold depression is not always by means of sensory neural hearing loss and sometimes it is an artifact caused by middle ear pathologies and ossicular chain problems. In this research, the influences of ear surgeries on bone conduction were evaluated.
  
  
  METHODS
  This study was conducted as a clinical trial study. The ear surgery performed on 83 patients classified in four categories: Stapedectomy, tympanomastoid surgery and ossicular reconstruction partially or totally; Partial Ossicular Replacement Prosthesis (PORP) and Total Ossicular Replacement Prosthesis (TORP). Bone conduction thresholds assessed in frequencies of 250, 500, 1000, 2000 and 4000 Hz pre and post the surgery.
  
  
  RESULTS
  In stapedectomy group, the average of BC threshold in all frequencies improved approximately 6 dB in frequency of 2000 Hz. In tympanomastoid group, BC threshold in the frequency of 500, 1000 and 2000 Hz changed 4 dB (P-value < 0.05). Moreover, In the PORP group, 5 dB enhancement was seen in 1000 and 2000 Hz. In TORP group, the results confirmed that BC threshold improved in all frequencies especially at 4000 Hz about 6.5 dB.
  
  
  CONCLUSIONS
  In according to results of this study, BC threshold shift was seen after several ear surgeries such as stapedectomy, tympanoplasty, PORP and TORP. The average of BC improvement was approximately 5 dB. It must be considered that BC depression might happen because of ossicular chain problems. Therefore; by resolving middle ear pathologies, the better BC threshold was obtained, the less hearing problems would be faced.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Farhad
authors.initials: F
authors.lastname: Mokhtarinejad
authors.affiliation: Department of Otorhinolaryngology, Head and Neck surgery, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Saeed Soheili
authors.initials: SS
authors.lastname: Pour
authors.affiliation: Department of Audiology, School of Rehabilitation Sciences, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mohammad Hussein
authors.initials: MH
authors.lastname: Nilforoush
authors.affiliation: Department of Audiology, School of Rehabilitation Sciences, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Sepehrnejad
authors.affiliation: Department of Otorhinolaryngology, Head and Neck surgery, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Susan
authors.initials: S
authors.lastname: Mirelahi
keywords: Bone conduction; hearing threshold improvement; partial ossicular replacement prosthesis; stapedectomy; total ossicular replacement prosthesis; tympanoplasty