IMAGE-GUIDED, ENDOSCOPIC-ASSISTED DRILLING AND EXPOSURE OF THE WHOLE LENGTH OF THE INTERNAL AUDITORY CANAL AND ITS FUNDUS WITH PRESERVATION OF THE INTEGRITY OF THE LABYRINTH USING A RETROSIGMOID APPROACH

Abstract

Frameless navigation using high-resolution computed tomographic scans and bone-implanted reference markers can provide a "roadmap" to maximize safe surgical exposure of the IAC without violating the labyrinth and leaving a small segment of the lateral IAC unexposed. Further exposure and surgical manipulation of this segment, including the fundus without additional cerebellar retraction and labyrinthine injury, can be achieved using an endoscope. Use of image guidance and an endoscope can help in exposing the entire posterior aspect of the IAC including its fundus without violating the labyrinth through a retrosigmoid approach. This technique could improve hearing preservation in vestibular schwannoma surgery.