Incidence of fallopian canal dehiscence at surgery for chronic otitis media

The objectives of this study were to determine the incidence and locations of dehiscence of the fallopian canal (FC) in patients undergoing surgery for different middle ear pathologies and to describe the findings that will aid in pre-operative prediction of dehiscence. Charts and operative details of the 118 ears managed with canal wall-down and 147 ears managed with canal wall-up tympanomastoidectomy performed by a single surgeon were retrospectively reviewed. The distribution of the diagnoses for ears that were operated was as follows: 118 ears cholesteatoma, 42 ears adhesive otitis, 23 ears tympanosclerosis, and 82 ears chronic otitis media. The presence and the location of facial nerve dehiscence after exenteration of the disease as well as the presence of any coexisting inner ear fistula and dural defect were noted. FC dehiscence was observed in 56 of the cases. The incidence of dehiscence was highest among ears with cholesteatoma ( n = 44, P