小脳橋角部手術操作による前庭神経損傷その発生機序に関する実験的検討

抄録

It is said that lateral-to-medial retraction of the cerebellar hemisphere is hazardous because it may cause avulsion injury of the cochlear nerve and internal auditory artery. Caudal-to-rostral retraction of the cerebellar hemisphere is, therefore, recommended in operations on the CP angle such as microvascular decompression procedures.
The results of our present study, however, show that caudal-to-rostral retraction can easily cause vestibular nerve damage, although rostral-to-caudal retraction may mainly damage the cochlear nerve as does lateral-to-medial retraction.
These differences of eighth nerve injuries according to the direction of cerebellar retraction can be explained by the fact that the vestibule and vestibular nerve are located posterior to the cochlea and cochlear nerve.
Most cases of dysequilibrium after manipulations in the CP angle area may be due to vestibular nerve damage-avulsion of the vestibular nerve and its accompanying vessels from the vestibular apparatus.