title: Unique microbiology of chronically unstable canal wall down tympanomastoid cavities: considerations for surgical revision.
abstract: OBJECTIVE
  To review the microbiology of open tympanomastoid cavities in patients who underwent revision surgery due to chronic instability.
  
  
  METHODS
  This paper describes a retrospective chart review of surgical revision cases of chronically unstable open mastoid cavities. Patient records from 2000 to 2010 were reviewed for the type of organism cultured, antimicrobial resistance and the presence of cholesteatoma.
  
  
  RESULTS
  In total, 121 revision surgical procedures were performed on 101 patients. Seventy-nine procedures involved culture specimen processing, 37 of which were positive. The most commonly cultured organism was Staphylococcus aureus, which was more than twice as common as any other pathogen. The presence of cholesteatoma had no impact on the likelihood of a positive culture or polymicrobial culture. Antimicrobial-resistant pathogens were uncommon.
  
  
  CONCLUSIONS
  A positive culture was not an overwhelmingly common characteristic of unstable tympanomastoid cavities. Furthermore, antimicrobial resistance did not appear to play an essential role in leading patients towards revision open mastoid surgery.
authors.affiliation: Department of Otolaryngology - Head and Neck Surgery, University of Arkansas for Medical Sciences, Little Rock, AK 72205,USA. michaelgluth@mac.com
authors.forename: M B
authors.initials: MB
authors.lastname: Gluth
authors.forename: B Y B
authors.initials: BY
authors.lastname: Tan
authors.forename: P L
authors.initials: PL
authors.lastname: Santa Maria
authors.forename: M D
authors.initials: MD
authors.lastname: Atlas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004432:Ear, Middle / Q000382:microbiology*; D006801:Humans; D008416:Mastoid / Q000382:microbiology* / Q000601:surgery*; D008875:Middle Aged; D011183:Postoperative Complications / Q000382:microbiology*; D012086:Reoperation; D012189:Retrospective Studies; D055815:Young Adult