面神经颅内段及管内段的应用解剖

Applied anatomy of intracranial and intracanal segments of facial nerve

目的：为颅底或中耳手术时防止伤及面神经管内段提供形态学依据,并积累中国人体质资料.方法：解剖测量15具正常人头颅标本的面神经颅内段、内耳道段、迷路段、鼓室段和乳突段长度和外径,并观察记录各段与周围结构的毗邻关系.具体观测包括三叉神经后外侧缘与面神经入内耳门处和岩大神经起点处的间隔;迷路动脉与前庭蜗神经和面神经的位置关系;膝神经节的形态和位置;岩大神经;鼓索的起始部位;面神经鼓室段与鼓膜内面的距离以及面神经乳突段与横窦和颈静脉孔间的距离等.结果：面神经颅内段、内耳道段、迷路段、鼓室段和乳突段长度依次为 （12.02±1.95）mm, （1 40±0.31）mm;（7.57±1.52）mm,（1.32±0 22）mm;（2.21±1.14）mm,（1.29±0.37）mm;外径依次为（7 .79±3.28）mm,（1.31±0.26）mm和（17.81±3.94）mm,（1 55±0.38）mm.结论：观测了面神经颅内段及管内段,各段的形态学特点及其与周围结构的毗邻关系,为颅底和颞骨（中耳、乳突等）手术时保护面神经提供了应用解剖学依据.

Objective： To provide anatomic data for the protection of intracanal facial nerve in the operations on the skull base or middle ear. Methods： The length and diameter of intracranial, meatal, labyrinthine, tympanic and mastoid segments of facial nerve were measured in normal adult heads taken from fifteen fixed cadavers, and adjacent relations between each segment and surrounding structures were observed. Results： The length and diameter of intracranial, meatal, labyrinthine, tympanic and mastoid segments of the facial nerve were （12.02±1.95） ram, （1.40±0.31） mm; （7.57±_1.52） mm, （1.32±0.22） mm; （2.21±1.14） mm, （1.29±0.37） ram; （7.79±3.28） ram, （1.31±0.26） remand （17.81±3.94） mm, （1.55±0.38） mm respectively. The following relations and structures were observed： the distance between the posterior lateral margin of trigeminal nerve; the site of facial nerve entering internal acoustic pore and the starting point of greater petrosal nerve; the position relation between labyrinthine artery, vestibulocochlear nerve and facial nerve; the shape and loca- tion of geniculate ganglion; the greater petrosal nerve; the start site of chorda tympani; the distance between tympanic segment of facial nerve and the internal surface of tympanic membrane, and the distance between mastoid segment and transverse sinus and jugular foramen. Conclusion： We observed morphologic characters, adjacent relations and surrounding structures of each segment in the facial nerve by anatomizing intracranial and intracanal segments in the facial nerve on cadaver sample. This paper provides some applied anatomy data on how to protect facial nerve in operations on the skull base and temporal bone.