[Three-dimensional reconstruction of internal auditory meatus and anatomical study of the inner structures].
OBJECTIVE
To provide anatomical basis for surgical operation in internal auditory meatus (IAM).


METHODS
Structures of cerebellopontine angle (CPA) and IAM in 25 temporal bone specimens (50 sides) fixed in formalin were measured. Three-dimensional reconstruction (3DR) of IAM in 13 normal adults (26 sides) was conducted using spiral CT scanning.


RESULTS
IAM took a conic shape with larger inside and smaller outside. The average width of IAM was (4.16 +/- 1.23) mm(2.87-6.83 mm) in horizontal dimension, the average height was (3.14 +/- 1.01) mm(2.23-4.45 mm) in vertical dimension, the average length was (8.67 +/- 2.31) mm (6.77-11.22 mm), the average volume was (98.23 +/- 16.56) mm3(67.44-133.21 mm3). There were 1-4 internal auditory arteries branched from the anterior-inferior cerebellar artery, which formed a vascular ansa near the opening of IAM. The average length of the facial nerve in IAM was (0.98 +/- 0.03) mm (0.89-1.07 mm), the average diameter of vestibulocochlear nerve was (1.67 +/- 0.05) mm (1.42-1.97 mm), the average diameter of the intermediate nerve (0.23 +/- 0.02) mm (0.19-0.26 mm).


CONCLUSIONS
It is necessary to pay attention to types of vascular ansa and relative nerve location in IAM during operation.
Chen
H
H
Department of Otorhinolaryngology, Nanfang Hospital, First Military Medical University, Guangzhou 510515, China. chhx@fimmu.edu.cn
Yu
C
C
Zhong
S
S
Wang
X
X
D000328:Adult; D000718:Anatomy, Regional; D007758:Ear, Inner / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000294:innervation; D005260:Female; D006801:Humans; D008297:Male; D036542:Tomography, Spiral Computed / Q000379:methods*