Endolymphatic sac surgery.

Class A results in Menière's disease.

A series of 101 patients with Menière's disease treated surgically with an intramastoid endolymphatic shunt operation and with a minimum follow-up of 2 years is reported. The results included success in 76 percent and failure in 22 percent. Thirteen of these patients maintained a hearing level of 15 dB or better, while 11 patients experienced hearing gains of 25 dB or better. These results are compared to other reports, and the difficulty of making such comparisons is illustrated. A derived "efficacy ratio" is defined, and its use is suggested to aid in making statistical inference. The conclusion is reached that more knowledge is required about the natural history of Menière's disease so that appropriate staging may be carried out on these study populations.