title: The pathogenesis of acquired cholesteatoma of the human middle ear:  support for the migration hypothesis.
abstract: OBJECTIVE
  That acquired cholesteatoma of the human middle ear and mastoid process can be caused by migration of squamous epithelium from the tympanic membrane.
  
  
  OBJECTIVE
  To provide histologic evidence in humans of the potential for medial epithelial migration toward the middle ear.
  
  
  BACKGROUND
  The origin of cholesteatomas of the middle ear complex of humans is still not clearly understood. The most popular theory, the medial migration of squamous epithelium from the external auditory canal/tympanic membrane through a perforation of the tympanic membrane to form a cholesteatoma, was first proposed over a century ago independently by Bezold (1899) and Habermann (1899) based on their observations during surgery. Neither author had histologic proof. Despite much experimental efforts in animals, histologic evidence in the human continues to be the missing link.
  
  
  METHODS
  We examined the histologic sections of the temporal bones of 60 children aged 1 day to 12 years with evidence of acute otitis media. We present our findings in the temporal bones of 3 infants.
  
  
  RESULTS
  We find evidence of the propensity of the squamous epithelium of the tympanic membrane particularly in the pars flaccida to become very active and to migrate medially toward the middle ear.
  
  
  CONCLUSIONS
  Our concept is that this material supports the migration theory that cholesteatomas are formed by the medial migration of the stimulated squamous epithelium of the tympanic membrane.
authors.affiliation: Department of Otolaryngology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA. ckarmody@tuftsmedicalcenter.org
authors.forename: Collin S
authors.initials: CS
authors.lastname: Karmody
authors.forename: Clarinda
authors.initials: C
authors.lastname: Northrop
mesh_terms: D002465:Cell Movement; D002648:Child; D002675:Child, Preschool; D018424:Cholesteatoma, Middle Ear / Q000382:microbiology / Q000473:pathology*; D004432:Ear, Middle / Q000473:pathology; D004848:Epithelium / Q000473:pathology; D004927:Escherichia coli Infections / Q000150:complications; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007642:Keratosis / Q000473:pathology; D008297:Male; D016920:Meningitis, Bacterial / Q000382:microbiology; D009504:Neutrophils / Q000502:physiology; D010035:Otitis Media, Suppurative / Q000382:microbiology / Q000473:pathology; D011014:Pneumonia / Q000382:microbiology; D018805:Sepsis / Q000150:complications / Q000188:drug therapy; D013701:Temporal Bone / Q000473:pathology; D014432:Tympanic Membrane / Q000473:pathology