Endoscope-assisted vestibular neurectomy

Objective/Hypothesis: In some instances endoscopes offer better visualizati on than the microscope and frequently allow less invasive surgery. This stu dy was undertaken 60 determine whether endoscopy is safe and effective duri ng neurectomy of the vestibular nerve. Method: Ten patients with intractabl e unilateral Meniere's disease underwent a retrosigmoid craniotomy for neur ectomy of the vestibular nerve. Endoscopy with a Hopkins telescope was used during each procedure to study posterior fossa anatomic relationships and to assist the neurectomy, Preoperative and postoperative audiometric evalua tion was performed in all patients undergoing vestibular neurectomy. Nine o f these patients had preoperative electronystagmography, and four patients completed postoperative electronystagmography. The 1995 American Academy of Otolaryngology-Head and Neck Surgery's Committee on Hearing and Equilibriu m guidelines for the diagnosis and evaluation of therapy in Meniere's disea se were used, Results: Complete neurectomy was achieved in all 10 patients. Endoscopy allowed improved identification of the nervus intermedius and th e facial, cochlear, and vestibular nerves and adjacent neurovascular relati onships without the need for significant retraction of the cerebellum or br ainstem. In addition, endoscopic identification of the cleavage plane betwe en the cochlear and vestibular nerves medial to or within the internal audi tory canal (n = 3) was not made with the 0-degree endoscope; however, ident ification was made with the 30- or 70-degree endoscope in all cases. In all patients with Meniere's disease, elimination of the recurrent episodes of vertigo (n = 10) or otolithic crisis of Tumarkin (n = 1) was achieved. Conc lusions: Posterior fossa endoscopy can be performed safely. Endoscope-assis ted neurectomy of the vestibular nerve may offer some advantages over stand ard microsurgery including increased visualization, more complete neurectom y, minimal cerebellar retraction, and a lowered risk of cerebrospinal fluid leakage.