A new method of patient's head positioning in suboccipital retrosigmoid approach

Background: The retrosigmoid approach is a common route to the cerebellopontine angle and lateral clivus. Patient′s head positioning just before the operation is crucial to perform the procedure effectively and safely.
Aim : The aim of the study is to determine the positional angle of the head on preoperative axial sequences of the cranial magnetic resonance imaging (MRI).
Materials and Methods : The angle between the line drawn along the petrous bone ventral to the internal auditory canal and the line drawn parallel to the dorsal face of the clivus on the axial view of MRI sequences was measured.
Results : This method of patient positioning has resulted in minimal cerebellar retraction, less time in the preoperative preparation period and less postoperative headache and neck pain.
Conclusions : This method can provide quick and better exposure of the cerebellopontine angle. Preoperative measurement of positional angle on axial MRI sequences is a very simple and sufficient way to determine the angle of the head that is turned to the contralateral side.

Keywords
Cerebellopontine angle, retrosigmoid approach, head positioning, positional angle