Suboccipital removal of vestibular neurinoma with preservation of the labyrinth.

Hearing preservation in surgery for vestibular neurinoma depends on several factors, the first of which is, of course, early diagnosis. If a small enough tumor is found in a patient with reasonable hearing, there is a fair chance that it can be removed in toto with preservation of some hearing. We report data from 40 operated patients; the question was whether the identification of the transverse crest and the removal of tumor from the lateral part of the internal auditory meatus could be achieved without opening of perilymph spaces. In most of these ears the angle from the medial edge of a suboccipital craniectomy allowed the surgeon a direct view of the lateral part of the internal auditory meatus with good exposure of the transverse crest without his having to open the labyrinth. So far we believe that loss of hearing caused during these operations is mainly due to the unfavorable location of the cochlear blood supply through the meatus.