Intracanalicular acoustic neuroma: early surgery for preservation of hearing.

Diagnosis of very small acoustic neuromas has become much more common since the advent of magnetic resonance imaging. Many of the patients so diagnosed have minimal unilateral hearing loss as their only symptom. Because limited information is available on the natural history and prognosis of these lesions, the choice of treatment is controversial. The authors review their recent experience with the surgical treatment of intracanalicular acoustic neuroma. The records of 14 consecutive patients with intracanalicular acoustic neuroma were reviewed with respect to type of presentation, pre- and postoperative facial and auditory nerve function, surgical approach, and complications. Detailed results for patients operated on to preserve hearing are presented. Presenting symptoms were nearly equally divided among diminished hearing, vertigo, and tinnitus. Eleven of the 14 patients had serviceable hearing preoperatively and nine (82%) remained in this condition postoperatively. Facial nerve function was unchanged by operation in 12 patients. Seven operations were performed through the middle fossa, five through the posterior fossa, and two by the translabyrinthine approach. The probability of preserving hearing during surgical excision of intracanalicular acoustic neuroma in patients with serviceable hearing exceeds 80%. Given the relative infrequency of serious complications and the likelihood of progressive hearing loss in the untreated patient, excision of such small tumors shortly after diagnosis may offer the best chance of long-term hearing preservation.