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

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

目的探讨内耳道底骨性结构及前庭神经、单孔神经骨管(神经管)的Micro-CT影像解剖学特征。方法取10%甲醛溶液固定的成人尸头标本6具(颞骨12侧), 其中男性4具、女性2具, 具体年龄不详。对12侧颞骨均行Micro-CT扫描, 再应用Mimics软件对内耳道底骨性结构及其中的神经管进行三维重建, 之后进行影像解剖学观察, 并分别测量前庭上神经、前庭下神经、单孔神经管相关解剖学参数。结果经Micro-CT扫描及三维重建, 内耳道底骨性结构及其内穿行的前庭神经和单孔神经管显示清晰。前庭上、下神经及单孔神经的解剖形态、位置及走行存在多种解剖变异以及多交叉分布现象。左右两侧前庭上神经管长度分别为(3.68±0.79)mm和(3.54±1.04)mm, 起始处前后径分别为(2.03±0.76)mm和(1.83±0.68)mm、上下径分别为(1.75±0.35)mm和(1.72±0.43)mm, 中点处的前后径分别为(0.89±0.19)mm和(1.13±0.29)mm、上下径分别为(1.58±0.26)mm和(1.69±0.58)mm;左右两侧前庭下神经管前后径分别为(0.44±0.07)mm和(0.50±0.29)mm, 上下径分别为(0.53±0.11)mm和(0.76±0.38)mm。左右两侧单孔神经管直线长度分别为(3.97±0.68)mm和(3.85±0.69)mm, 其内侧段长度分别为(2.54±0.70)mm和(2.26±0.82)mm、外侧段长度分别为(1.82±0.57)mm和(1.99±0.39)mm, 内侧段直径分别为(0.67±0.10)mm和(0.66±0.09)mm、外侧段直径分别为(0.47±0.04)mm和(0.51±0.10)mm, 内外段交角分别为128.82°±17.23°和127.51°±11.70°。以上各指标测量值侧别间比较, 差异均无统计学意义(P值均>0.05)。结论 Micro-CT扫描及三维重建可清晰显示内耳道底骨性结构及前庭神经、单孔神经骨管等结构及其空间位置与走行;前庭神经和单孔神经骨管解剖形态及位置、走行均存在较大变异, 但左右侧别间相关解剖学测量结果无差异。

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.