title: Improvement of eustachian tube function by tissue-engineered regeneration of mastoid air cells.
abstract: OBJECTIVE
  Most cases of chronic otitis media (OMC) are associated with poor development of the mastoid air cells (MACs) and poor Eustachian tube (ET) function. We have previously reported that MAC regeneration can effectively eliminate intractable OMC. In this study, we assessed the ability of regenerated MACs to restore normal gas exchange function and contribute to improved ET function.
  
  
  METHODS
  Clinical trial with control.
  
  
  METHODS
  General hospitals.
  
  
  METHODS
  Seventy-six patients with OMC, including cholesteatoma and adhesive otitis media, received tympanoplasty and MAC regeneration therapy. At the first-stage of tympanoplasty, artificial pneumatic bones and/or autologous bone fragments were implanted into the opened mastoid cavity. At the 2nd-stage operation, a nitrous oxide (N2O) gas study was performed in 10 patients to measure middle ear pressure (MEP). For the control group, MEP was measured in five patients with good MAC development during cochlear implantation or facial nerve decompression. ET function was measured twice in each patient, once before the 1st operation and 6 months after the second operation.
  
  
  RESULTS
  At the 2nd-stage operation, in all cases with regenerated MACs and in the normal control group, MEP changed after administration of N2O. In contrast, no change in MEP was observed in cases with unregenerated MACs. In 70% (n = 37/53) of the regenerated MAC group, ET function was improved, whereas improvement of ET function was observed in only 13% (n = 3/23) of the unregenerated MAC group.
  
  
  CONCLUSIONS
  Tissue-engineered regeneration of MACs improves ET function and gas exchange in the middle ear.
authors.affiliation: Department of Otolaryngology, The Foundation for Biomedical Research and Innovation, Kobe, Japan. kanemaru@ent.kuhp.kyoto-u.ac.jp
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Kanemaru
authors.forename: Hiroo
authors.initials: H
authors.lastname: Umeda
authors.forename: Masaru
authors.initials: M
authors.lastname: Yamashita
authors.forename: Harukazu
authors.initials: H
authors.lastname: Hiraumi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Hirano
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Nakamura
authors.forename: Juichi
authors.initials: J
authors.lastname: Ito
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D018424:Cholesteatoma, Middle Ear / Q000503:physiopathology / Q000601:surgery; D002908:Chronic Disease; D005064:Eustachian Tube / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008416:Mastoid / Q000166:cytology*; D008875:Middle Aged; D010033:Otitis Media / Q000601:surgery*; D012038:Regeneration; D023822:Tissue Engineering; D016896:Treatment Outcome; D014433:Tympanoplasty