Computed tomographic analysis of anatomic structure related to the infralabyrinthine approach to the internal auditory canal / 中国耳鼻咽喉头颈外科

ABSTRACT

OBJECTIVE To provide computed tomographic reference for the infralabyrinthine approach to the internal auditory canal.METHODS Temporal bone CT images of forty patients(80 sides) were randomly selected without ear lesions,and some relative structures were observed and measured.RESULTS The mean distance from the inferior edge of the posterior semicircular canal to the superior edge of the jugular bulb was (4.69±2.91)mm left and (3.10±3.01)mm right,the mean thickness of the bone inferior to the posterior semicircular canal was (0.92 ± 0.37)mm left and (0.69 ± 0.37)mm right,the mean distance from the vertical portion of the facial nerve to the anterior edge of the sigmoid sinus was (8.66±2.71)mm left and (7.74± 1.99)mm right,the mean distance from the superior edge of the jugular bulb to the internal auditory canal was (6.32 ± 2.88)mm left and (5.39 ± 2.61) mm right,the mean distance from the superior edge of the jugular bulb to the single foramen was (6.82 ± 3.02)mm left and (5.84 ± 2.82)mm right,the mean distance from the external aperture of vestibular aqueduct tothe posterior edge of internal acoustic porus was (14.38 ± 2.56)mm left and (14.12±2.76)mm right,the mean distance from the external aperture of vestibular aqueduct tothe midpoint of internal auditory canal was (12.02 ± 2.46)mm left and (11.91 ± 2.53)mm right.There were statistical differences in distances of different sides among the anterior three groups,no statistical differences were seen in distances of different sides among the posterior four groups.CONCLUSION The temporal bone CT images are helpful to the infralabyrinthine approach to the internal auditory canal.