Causes of failure of combined approach tympanoplasty in the treatment of acquired cholesteatomas of the middle ear and the mastoid.

Forty cases of failed combined approach tympanoplasty were analysed. The commonest cause of failure was adhesions between the facial ridge and the tympanic membrane, causing segmental attico-mastoid malaeration in 51.3 per cent of cases followed-up continually. Other causes were, large dermoids, incomplete removal of squamous epithelium, and eustachian tube obstruction. Eustachian tube dysfunction did not appear to be a major cause of failure.