The surgical anatomy and approach to the internal audiotory canal through the transmeatal route is presented. 2. The results of 22 patients undergoing transmeatal labyrinthectomy with cochleovestibular neurectomy indicated that 15 of 20, or 75 percent, had vertigo cured or markedly improved. The best results were found in patients with Ménière's disease (10/10). 3. Similar results were found regarding the symptoms of tinnitus. Fifteen of 22 patients, or 68 percent, had tinnitus cured or markedly improved in a six-month to 36-month follow-up. The best results, again, were found in patients with Ménière's disease (8/10). 4. Patients undergoing transmeatal labyrinthectomy without cochleovestibular neurectomy showed only one of six cases with improvement of tinnitus and three of six cases with vertigo cured or markedly improved. 5. Transmeatal labyrinthectomy with cochleovestibular neurectomy appears to have the following advantages over transmeatal labyrinthectomy or translabyrinthine section of the VIIIth nerve: a. The surgical time is shortened by the direct route to the internal auditory canal. b. A second procedure is avoided by not having to obtain abdominal adipose tissue for obliteration of the mastoid cavity. c. Complete unilateral ablation of vestibular function is assured. d. Best chance of alleviation or improving tinnitus. e. The internal auditory canal is routinely inspected to be sure no acoustic neuroma or other pathology is found. f. Skill is obtained in transecting the "singular nerve."
