Abstract
Bony deficiency of the tegmen tympani has been found in cases of fatal intracranial complifications following air insufflation of the middle ear.This study set out to discover the incidence and appearance of such deficiencies. Sevently bones were examined and twenty per cent of them had tegmental deficiencies. There was no evidence of erosive disease in any of the bones.Reverse Politzerization following myringotomy has come to be regarded as a potentially dangerous procdure. It is also possible for infection to spread from the middle ear to the meninges, or for C.S.F. to leak into the middle ear from above.