颞骨内面神经垂直段的显微解剖及其临床意义

目的：研究颞骨内面神经垂直段及其毗邻结构的显微解剖,为临床应用提供解剖学资料。方法：通过模拟临床经乳突入路的方法,分层解剖20个成人湿性头颅标本（40侧颞骨）,显露并观测颞骨内面神经垂直段及其毗邻结构。结果：面神经垂直段的长度为（17.39±1.78）mm、直径为（2.13±0.13）mm,面神经垂直段与水平段的夹角（向前）为（115.5±6.89）°,面神经垂直段近端至外半规管隆突距离为（2.86±0.31）mm,鼓索神经自面神经发出点至茎乳孔距离为（5.99±0.74）mm,面神经垂直段与鼓索神经的夹角（向上）为（38.6±1.99）°,锥隆起尖到面神经垂直段垂直距离为（2.05±0.65）mm,后半规管至面神经垂直段最短距离为（2.89±0.36）mm。有5%（2/40侧）的面神经垂直段的近端位于外半规管隆突外侧。结论：外半规管、鼓索神经、茎乳孔、锥隆起、后半规管是手术中确定面神经垂直段的重要标志。熟悉颞骨内面神经垂直段与其周围结构的毗邻关系,有利于面神经垂直段相关手术的顺利进行。

Clinical Significance and Microanatomy of Vertical Segment of Facial Nerve in Temporal Bone

Objective： To study microanatomy of vertical segment of facial nerve（FN） beside inner surface of temporal bone and its adjacent structures,in order to provide anatomic data for clinical application.Methods： The vertical segments of FN beside inner surface of temporal bone and their adjacent structures were observed in 20 adult wet skull specimens（40 temporal bones） by simulating traditional clinical operation via transmastoid approaches.Results： The mean length of vertical segments was（17.39±1.78）mm,its diameter was（2.13±0.13）mm.The angle between vertical and horizontal segments was（115.5±6.89）°.The distance from the proximal end of FN vertical segment to the eminence of lateral semicircular canal was（2.86±0.31）mm.The distance between stylomastoid foramen and the point from which chorda tympani nerve departed FN was（5.99±0.74）mm;The angle of chorda tympani nerve and FN vertical segment was（38.6 ± 1.99）°;The vertical distance from the top of pyramidal eminence to FN vertical segment was（2.05±0.65）mm;The shortest distance between vertical segment and posterior semicircular canal was（2.89±0.36）mm.There were 5%（2/40）of proximal part of FN vertical segment tracking forwards the lateral of eminence of lateral semicircular canal.Conclusions： Lateral semicircular canal,chorda tympani nerve,stylomastoid foramen,pyramidal eminence and posterior semicircular canal are important landmarks by which FN vertical segment might be ascertained during operation.Having familiar with anatomical relationship between FN vertical segments and their adjacent structures in temporal bones,would profit the operations involving FN vertical segment.