Endolymphatic sac surgery: methods of study and results.

Surgery of the endolymphatic sac (ELS) in classical Meniere's disease has fallen under attack and has been abandoned by some surgeons. We studied our results for vertigo and hearing in 83 patients undergoing surgery of the ELS for intractable classical Meniere's disease. Half of the patients were completely free of definitive attacks at 2 years; another quarter experienced substantial control. Three fourths noted an improvement in their level of disability. Results for vertigo were sustained at longer follow-up intervals. Nineteen percent had revision surgery (usually retrolabyrinthine vestibular neurectomy) for intractable vertigo within 2 years of the sac operation. The 1985 reporting method of the American Academy of Otolaryngology--Head and Neck Surgery was found superior to previous methods because it specified a meaningful follow-up interval, used a graded scale accounting for partial success in treatment, and separated results for vertigo and hearing. Nevertheless, optimal use of the method in the future will require prospective reporting and a concerted effort to avoid confusion between definitive attacks of true vertigo and adjunctive vestibular symptoms. Even though the mechanism of the beneficial effect of sac surgery is unknown, we have found it useful in the control of disabling vertigo.