Translabyrinthine resection of the small acoustic neuroma.

Abstract

THE SMALL acoustic neuroma with coexisting loss of serviceable auditory function is best removed by way of the translabyrinthine route. This is a relatively short operation with a low morbidity and mortality rate.^1,2It offers the best opportunity to preserve facial nerve function.^3-6Certainly it is the only approach lending accessibility to the intrameatal and petrous extensions of the tumor. Larger tumors can be safely resected with preservation of the facial nerve by the staged translabyrinthine-suboccipital approach. The key to this surgical technique is a thorough knowledge of the anatomy of the petrous bone and its surrounding structures.⁷ The mastoid, middle ear, and labyrinth have been dissected in Fig 1,<i>top</i>. The important relationships of the horizontal portion of the facial nerve are the processus cochlearformis, incudal fossa, and the horizontal semicircular canal. The ampullar ends of the horizontal and superior semicircular canals are close neighbors. The