Bell's palsy: surgery based upon prognostic indicators and results.

We studied 164 patients with Bell's palsy prospectively over the six-year period between August 1974 and June 1980. We found that the results of measuring tear production, submandibular salivary flow, the response to maximal stimulation, and evoked electromyography gave us sufficient information to group these patients according to prognosis--either unfavorable or favorable--for spontaneous return of facial function. When the test results were 26% or more of normal, 90% of the patients had complete recovery of function; these patients were given a favorable prognosis on the basis of the results of tests described above. The natural history of Bell's palsy in patients with an unfavorable prognosis could be improved if a transmastoid facial nerve decompression to the labyrinthine segment were performed. The results were better with this approach than with supportive or steroid therapy or transmastoid vertical-horizontal surgical decompression of the facial nerve.