Surgical anatomy for central auditory device implantation
Reviewed by Gauri Mankekar

This cadaveric study by researchers in the USA and Japan examined the cerebellopontine angles with the aid of the surgical microscope and 45o endoscope via the retrosigmoid and translabyrinthine approach. Using fibre dissection technique, the ascending auditory pathways between the cochlear nuclei and inferior colliculi and above were examined. The authors report that both the translabyrinthine and retrosigmoid routes provide adequate exposure for concurrent removal of tumour and implantation of the auditory brain stem device at either the cochlear nuclei or inferior colliculus. They also found that if the cochlear nuclei are not functionally or structurally suitable for implantation, then the inferior colliculus is an alternative site for implantation due to its accessibility via both the approaches as well as due to its position in the auditory pathways. This study provides an excellent description of the anatomy and surgical approaches to the cochlear nucleus complex and the inferior colliculus. This surgical knowledge is very important for surgeons planning to place central auditory prostheses, which are becoming increasingly popular due to their improving results. 

Auditory brainstem implantation: anatomy and approaches.
Komune N, Yagmurlu K, Matsuo S, Miki K, Abe H, Rhoton AL.
NEUROSURGERY
2015;S11(2):306-21.