title: Volumetric Changes in the Bony External Auditory Canal in Unilateral Chronic Otitis Media.
abstract: OBJECTIVE
  Pneumatization of air cells in the mastoid bone is decreased in chronic otitis media (COM). A decrease in the size of the external auditory canal (EAC) is also found frequently in patients with COM, but this has been little studied. We compared the size of affected bony EACs and the contralateral side in patients with single-side COM using high-resolution computed tomography.
  
  
  METHODS
  In total, 99 patients with single-side COM were included. Four indicators related to the size of the bony EAC and IAC were measured using high-resolution computed tomography: the axial and coronal lengths of the tympanic membrane, the length of the isthmus, and the area of the bony ear canal. We also compared both internal auditory canals as negative controls. These assessments were made by radiologists who were blinded to the objective of this study.
  
  
  RESULTS
  In patients with single-side COM, the axial length of the tympanic membrane was significantly shorter than normal, and the volume of the EAC was also significantly smaller. The length of the isthmus of the EAC was shorter on the affected side, but the difference was not significant. The IAC volume showed no difference between the two sides.
  
  
  CONCLUSIONS
  COM affects general temporal bony development, including the bony EAC and mastoid bone. Therefore, whether to correct this should be considered when preparing for COM surgery.
authors.affiliation: Department of Otorhinolayrngology-Head and Neck Surgery, Soonchunhyang University School of Medicine, Cheonan, Korea.
authors.forename: Jae Hong
authors.initials: JH
authors.lastname: Park
authors.affiliation: Department of Otorhinolayrngology-Head and Neck Surgery, Soonchunhyang University School of Medicine, Cheonan, Korea.
authors.forename: MinHo
authors.initials: M
authors.lastname: Noh
authors.affiliation: Department of Otorhinolayrngology-Head and Neck Surgery, Soonchunhyang University School of Medicine, Cheonan, Korea.
authors.forename: Chi-Kyou
authors.initials: CK
authors.lastname: Lee
authors.affiliation: Department of Otorhinolayrngology-Head and Neck Surgery, Soonchunhyang University School of Medicine, Cheonan, Korea.
authors.forename: Seung Bum
authors.initials: SB
authors.lastname: Park
authors.affiliation: Department of Otorhinolayrngology-Head and Neck Surgery, Soonchunhyang University School of Medicine, Cheonan, Korea.
authors.forename: Kye Hoon
authors.initials: KH
authors.lastname: Park
authors.affiliation: Department of Radiology, Soonchunhyang University School of Medicine, Cheonan, Korea.
authors.forename: Jong Kyu
authors.initials: JK
authors.lastname: Han
authors.affiliation: Department of Radiology, Soonchunhyang University School of Medicine, Cheonan, Korea.
authors.forename: Hyun Jeong
authors.initials: HJ
authors.lastname: Kim
keywords: Computed tomography; External auditory canal; Otitis media