[Topographo-anatomic basis of the translabyrinthine approach to the internal auditory canal and the cerebellopontile angle].

Microanatomical study of temporal bone structures and modelling of the translabyrinthine approach (70 specimens) showed that the approach provides extradural access to the internal acoustic meatus and cerebellopontine angle without injury to the nerve structures by stage-by-stage removal of the bony structures of the petrous part of the temporal bone. With this approach the dura mater covering the posterior surface of the internal acoustic meatus can be exposed for its entire length as well as an area of the dura mater of the posterior cranial fossa. The authors revealed considerable variations in the position of temporal bone structures which are the boundaries of the operative field and in the possible microsurgical manipulations in the translabyrinthine approach and removal of the tumor.