Table 1:

Classification of all cholesteatomas based on pathogenesis

Initial LocationClinical HistoryStatus of TM (if middle ear)
Congenital (2%)aAnywhere in the temporal boneNo historyIntact
AcquiredMiddle earRecurrent ear disease
    Primary (80%)aApparently intact
    Secondary (18%)aPerforated

  • a The percentage refers to the distribution of cholesteatomas in the middle ear.