An anatomic study of modified infralabyrinthine approach to the internal auditory canal / 中国耳鼻咽喉头颈外科

ABSTRACT

OBJECTIVE To study the modified infralabyrinthine approach in order to open the internal auditory canal,and to provide anatomic reference.METHODS In this study,the modified infralabyrinthine approach was performed on 10 adult cadaver heads(20 sides temporal bones),and some relative structures were observed and measured.RESULTS The posterior wall of internal auditory canal was opened successfully in 16/20 sides temporal bones via the modified infralabyrinthine approach,the average exposure length was (72.44 ± 14.19)％ of the whole length of the internal auditory canal.The mean distance from the inferior edge of the posterior semicircular canal to the superior edge of the jugular bulb was (4.60 ± 3.47) mm,the mean distance from the vertical portion of the facial nerve to the anterior edge of the sigmoid sinus in the infralabyrinthine area was (8.40 ± 2.74) mm,the mean distance from the superior edge of the jugular bulb to the internal auditory canal was (5.88±2.88) mm,the mean distance from the superior edge of endolymphatic sac to the internal auditory canal was (13.24±3.41) mm.CONCLUSION The modified infralabyrinthine approach had the advantages of tiny trauma and the disadvantages of more difficulty,if we selected suitable cases and prepared sufficiently,the surgery could be achieved safely and effectively.