Abstract
From 1971 to 1984, 27 patients with Mdniere's disease were treated surgically at Kitasato University Hospital. The 15 treated with Rosen's operation, section of the chorda tympanic nerve, had frequent recurrences of vertigo soon after surgery. In nine of these patients the attacks stopped within one year after the operation, in three patients they stopped one to two years and in one patient two to three years after surgery. However, in four patients vertigo recurred later. In two patients the operation had no effect.
Of the 10 patients treated with Portmann's endolymphatic sac operation, success was achieved in only five : cessation of attacks of vertigo and preservation or improvement of hearing. All three patients treated with labyrinthectomy after Rosen's operation, had trouble later in the nonoperated ear.
A new metdod of determining the efficacy of treatment was devised microcomputer to measure the differences in the mean interval between two successive attacks and in the mean hearing level before and after treatment. These were evaluated statistically at the level of 5% error.
