title: A new pathogenesis of mesotympanic (congenital) cholesteatoma.
abstract: OBJECTIVE
  To introduce a new, acquired pathogenetic theory of mesotympanic cholesteatoma behind an intact eardrum in children and to present some doubts on congenital pathogenesis.
  
  
  METHODS
  Literature review.
  
  
  METHODS
  The incidence and origination of mesotympanic cholesteatoma in children were thoroughly analyzed in the world literature and correlated to the histopathological studies on human middle ear epithelia and to epidemiological studies on secretory otitis, tubal occlusion, and acute suppurative otitis media.
  
  
  RESULTS
  The new, acquired theory is based on the fact that that the place of origin of the anterosuperior mesotympanic cholesteatoma is the area of the malleus handle and malleus neck, and of the posterosuperior cholesteatoma, the long process of the incus. During the common pathological conditions there is a great risk of retractions and adhesions of the eardrum to these ossicles. After subsequent loosening of the retracted eardrum some cells of the keratinized squamous epithelium may be left behind and become included into the tympanic cavity, eventually causing an inclusion cholesteatoma. Four basic mechanisms of inclusions are proposed and the presence of great dynamics in middle ear disease in children, with high incidence of tubal dysfunction, retractions, secretory otitis, and acute suppurative otitis, is documented, making the acquired pathogenesis probable. The place of origin does not fit with the congenital pathogenesis of epithelial formation localized on the lateral wall of the eustachian tube close to the annulus. The origination around the malleus and incus fits better with the proposed acquired pathogenesis.
  
  
  CONCLUSIONS
  There are no definitive proofs for the acquired pathogenesis of the mesotympanic cholesteatoma, nor is there experimental research to prove or disprove it. Mesotympanic cholesteatoma, congenital cholesteatoma, acquired pathogenesis of mesotympanic cholesteatoma, cholesteatoma in children, cholesteatoma behind intact eardrum.
authors.affiliation: Department of Otolaryngology, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark.
authors.forename: M
authors.initials: M
authors.lastname: Tos
mesh_terms: D002648:Child; D018424:Cholesteatoma, Middle Ear / Q000151:congenital* / Q000453:epidemiology / Q000473:pathology; D004432:Ear, Middle / Q000196:embryology; D006801:Humans; D015994:Incidence