Promontory stimulation following translabyrinthine excision of acoustic neuroma with preservation of the cochlear nerve.

Promontory stimulation is an accurate method of assessing the functional integrity of the cochlear nerve by electrical stimulation. This technique is widely used in screening prospective candidates for cochlear implants. Recent reports have confirmed the integrity of cochlear nerve responses to electrical stimulation following labyrinthectomy and unsuccessful hearing preservation attempt by the retrosigmoid approach. In this report, the authors present three patients with intracanalicular acoustic neuromas excised through a translabyrinthine approach in which the cochlear nerve was preserved. In each patient, promontory stimulation elicited repeatable behavioral responses. These responses were consistent over a 9-month period of observation.