Imaging anatomy research of the bone structure together with vestibular nerve and singular nerve bony canal in the fundus of internal auditory meatus observed by Micro-CT scanning
Li Qiuhuan1, Xie Jiaojiao2, Zhao Xiaochang3, Jiang Zigang1, Yu Zilong4
1Department of Otology, the First Hospital of Qinhuangdao, Qinhuangdao 066000, China; 2Department of Otolaryngology Head and Neck Surgery, Beijing Luhe Hospital Affiliated Capital Medical University, Beijing 101199, China; 3Department of Otolaryngology Head and Neck Surgery, Beijing Chaoyang Hospital Affiliated Capital Medical University, Beijing 100020, China; 4Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital Affiliated Capital Medical University, Beijing 100730, China
Abstract：Objective This study aims to investigate the micro-CT imaging anatomical features of the bony structures of the fundus of internal auditory meatus and bony neural canals (neural canal) including vestibular nerve canal and singular nerve canal. Methods Six adult cadaver heads including four males and two females were fixed with 10% formaldehyde solution. Twelve sides of temporal bone were scanned by micro-CT. The bony structures and bony neural canals of the fundus of internal auditory meatus including vestibular nerve and single foramen nerve canals were reconstructed by Mimics software. The anatomical parameters of superior vestibular nerve, inferior vestibular nerve, and single foramen nerve canals were measured. Results The bony structures of the fundus of internal auditory meatus and the neural canals including vestibular nerve and singular nerve canals traveling through the fundus of internal auditory meatus were displayed by micro-CT scanning and three-dimension reconstruction. Extensive anatomical variations and multi-crossing distribution were found in superior vestibular nerve, inferior vestibular nerve, and singular nerve canals between different sides and individuals. The length, antero-posterior diameter, and superior-inferior diameter at origin point of the superior vestibular canal were (3.68±0.79) mm, (2.03±0.76) mm, and (1.75±0.35) mm on the left side and (3.54±1.04) mm, (1.83±0.68) mm, and (1.72±0.43) mm on the right side, respectively. The antero-posterior diameter and the superior-inferior diameter of superior vestibular canal at the midpoint of the superior vestibular canal were (0.89±0.19) and (1.58±0.26) mm on the left side and (1.13±0.29) and (1.69±0.58) mm on the right side, respectively. The antero-posterior diameter of inferior vestibular canal on the left and right sides were (0.44±0.07) and (0.50±0.29) mm, respectively, and the superior-inferior diameters of inferior vestibular canal on the left and right sides were (0.53±0.11) and (0.76±0.38) mm, respectively. The straight line length of single foramen neural tube on the left and right sides were (3.97±0.68) and (3.85±0.69) mm, respectively, the length of the medial segment on the left and right sides were (2.54±0.70) and (2.26±0.82) mm, and the length of the lateral segment on the left and right sides were (1.82±0.57) and (1.99±0.39) mm, respectively. The diameters of the medial and lateral segments were (0.67±0.10) and (0.47±0.04) mm on the left side and (0.66±0.09) and (0.51±0.10) mm on the right side, respectively, and the intersecting angles of the medial and lateral segments on the left and right sides were 128.82°±17.23°and 127.51°±11.70°. No significant difference in the measured values of the above indices was found among different sides (all P values>0.05). Conclusion Micro-CT scanning and three-dimensional reconstruction can clearly show the bony structures of the fundus of internal auditory meatus, vestibular nerve, and single foramen nerve canals as well as their spatial location and course. The anatomical morphology, position, and course of vestibular nerve and single foramen nerve have great variations, but the anatomical measurements have no significant difference between the left and right sides.
李秋焕, 解佼佼, 赵晓畅, 姜子刚, 于子龙. 内耳道底骨性结构、前庭神经与单孔神经骨管的Micro-CT影像解剖学实验研究[J]. 中华解剖与临床杂志, 2023, 28(3): 153-158.
Li Qiuhuan, Xie Jiaojiao, Zhao Xiaochang, Jiang Zigang, Yu Zilong. Imaging anatomy research of the bone structure together with vestibular nerve and singular nerve bony canal in the fundus of internal auditory meatus observed by Micro-CT scanning. Chinese Journal of Anatomy and Clinics, 2023, 28(3): 153-158.
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2023, Vol. 28 
