A systematic approach to the surgical management of acoustic neuroma.

Contemporary otomicrosurgical techniques have made total removal of acoustic tumor with preservation of the seventh and sometimes the eighth cranial nerves possible. The four approaches currently used in acoustic tumor surgery are the middle cranial fossa, the translabyrinthine, the suboccipital, and the combined translabyrinthine-suboccipital. This review examines the surgical results in the removal of more than 600 acoustic tumors and outlines a rationale for the choice of approach. Tumor size on computed tomographic scan and auditory reserve establish the parameters used in planning the surgical procedure. The translabyrinthine exposure is used most frequently followed by the combined translabyrinthine-suboccipital. The middle fossa and suboccipital approaches are used when preservation of hearing is attempted. Total removal of tumor was accomplished in more than 99% of patients with a mortality rate of less than 1%. Anatomic preservation of the facial nerve, which is directly related to tumor size, was achieved in more than 80% of patients. Preservation of hearing is unlikely when the tumor is larger than 2 cm; anatomic preservation of the cochlear nerve was successful in 73% of hearing preservation procedures.