[Endoscopy of the cerebellopontile angle using the retrosinusal-suboccipital route].

In spite of the introduction of new examination methods (positive contrast demonstration, tomography, CAT) difficulties may be encountered in the instrumental diagnosis of smaller neurinomas of the auditory nerve. That is why one has already for some time tried to reach the pontine-angle with the endoscope. Until now, this has been done by the transpyramidal-retrolabyrinthal route. Since this access is too complicated for diagnostic purposes, the authors have chosen the retrosinal-suboccipital route and proved its suitability by examinations in corpses. This is the same route of access which is used by most neurosurgeons for carrying out operations to the pontine-angle tumour.