内耳道内神经间吻合及位置关系的显微解剖研究

Microscopic anatomy of the anastomosis and topographical relationship of nerves in the human internal auditory canal

目的探讨内耳道内神经走行及相互吻合关系。方法在手术显微镜下对30例成人颞骨标本进行显微解剖学研究,观察神经走行、面神经与前庭神经之间的吻合及耳蜗神经与前庭神经之间的吻合。结果(1)30例颞骨标本中,37%(11例)的面神经在内耳道内一直在前上位置;63%(19例)的面神经从内耳道底至内耳道口过程中均有围绕前庭神经纵轴不同程度的向前下旋转,旋转范围大致在30°～90°之间,旋转的方向与耳蜗旋转的方向相同。(2)30例标本中,17%(5例)的标本没有发现前庭神经与面神经吻合支;83%(25例)的面神经与前庭神经之间存在吻合支,并且形态和数目存在差异。67%(16例)的吻合支在接近内耳道口部位;33%(8例)的吻合支在接近内耳道底的外1/3的内耳道内。吻合支直径不等,约在0.5～1mm之间。(3)30例标本中,80%(24例)存在前庭耳蜗神经吻合支。在内耳道外1/3部位,13例标本中可明显看到一些刷状的神经纤维束直接进入球囊,15例在内耳道外1/3段有横行的吻合支,2例标本可以看到有多个吻合支,部分为两种形式共存。仅在内耳道中段有吻合支者1例;20%(6例)的标本未见有明显的前庭耳蜗神经吻合。结论在内耳道内,神经走行关系及神经之间的吻合均存在着个体差异。熟悉这些关系有助于手术中保护神经功能,以及探讨面神经、前庭及耳蜗疾病之间的关系。

Objective To investigate the topographical relationship and anastomosis of nerves in the human internal auditory canal, Methods We dissected 30 human temporal bones from 15 heads in order to examine the topographical relationship and anastomosis of nerves in the internal auditory canal, Results （1） In 11 temporal bones, the facial nerves coursed anterosuperior to the vestibulocochlear nerve in the whole portion of the internal auditory canal, In 19 temporal bones, the facial nerves rotated 30° - 90° to the anteroinferior direction along the course from the fundus of the internal auditory canal to the porus acusticus, similar to that of the cochlea, （2） Vestibulo-facial anastomosis occurred in 25 cases, of which 67% occurred near the porus acusticus, 33% between the fundus and the intermedial portion of the internal auditory canal, The diameter of the anatomosis was about 0.5 - 1 mm. （3） Vestibulocochlear anastomosis occurred in 24 cases, some of which appeared as a brush-like nerve fiber bundle of the cochlear nerve entering the sacculus directly （13 cases）, Transverse vestibulocochlear anastomosis in the fundus of the internal acoustic meatus occurred in 15 cases, including 2 cases with more than one anastomoses, No vestibulocochlear nerve anastomosis were found in 6 cases in this study, Conclusion The vestibulo-facial and vestibulocochlear anastomosis exists in the human internal auditory canal, They are heterogeneous, the same as the topographical relationship of the facial and acoustic nerves.