title: [Erosion of the mastoid caused by the external auditory canal cholesteatoma (with 3 cases reported)].
abstract: OBJECTIVE
  To improve the diagnosis and treatment of the external auditory canal cholesteatoma (EACC) with erosin into the mastoid.
  
  
  METHODS
  The data of 3 patients with erosin of the mastoid caused by EACC were analysed retrospectively and recent literatures were reviewed.
  
  
  RESULTS
  In all cases, the cholesteatomas were found in the external auditory canal and the mastoid cavity. The disease eroded the posterior aspect of the canal wall, and fistulas between the canal and the mastoid were found. The fallopian canal was eroded but the facial never and labyrinth were intact. All patients were treated with canal wall down mastoidectomy. There was no recurrence after 6 months to 9 years follow-up.
  
  
  CONCLUSIONS
  EACC was easily misdiagnosed as keratosis obturans(KO). EACC with posterior canal wall-mastoid cavity fistula is an extremely rare occurrence. Treatment consists of the removal of the cholesteatoma sac and bony sequestra. Surgical treatment options can be taken depending on the stage of disease.
authors.affiliation: Department of Otolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022.
authors.forename: Lixin
authors.initials: L
authors.lastname: Zhu
authors.forename: Shiying
authors.initials: S
authors.lastname: Liu
authors.forename: Jibao
authors.initials: J
authors.lastname: Wang
mesh_terms: D002781:Cholesteatoma / Q000175:diagnosis / Q000601:surgery*; D004424:Ear Canal / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008416:Mastoid / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D012189:Retrospective Studies