耳内镜下新西兰兔中耳的解剖研究

目的　耳内镜下观察兔中耳解剖结构，探讨兔作为耳内镜解剖训练模型的可行性，为兔中耳相关的其他实验研究提供解剖学依据。 方法　5只（10耳）新西兰兔麻醉处死后，耳内镜下经外耳道入路观察兔鼓膜、中耳鼓室结构，辨别听小骨、上中下鼓室、面神经等。 结果　与人对比，新西兰兔听小骨由锤砧联合体和镫骨组成；上鼓室外侧壁部分骨质缺如，由鼓膜向上延续并覆盖；听泡类似于人的中、下鼓室，包含咽鼓管、面神经、鼓岬、前庭窗、蜗窗以及鼓室神经等结构，乳突为听泡尾侧的板障型骨管；面神经鼓室段水平走行于上鼓室下方骨壁内，后经锥隆起垂直走行于听泡后壁，经茎乳孔出听泡。 结论　新西兰兔中耳结构与人相似，既可作为耳科医生练习耳内镜操作的解剖模型，也可作为耳部三维解剖结构的教学标本。

Anatomical study on middle ear of New Zealand rabbits by transcanal endoscopy

Objective To observe the anatomical structure of rabbit’s middle ear under ear endoscope and explore the feasibility of the rabbit as endoscopic anatomical training model of middle ear,and then provide anatomic base for other experimental research on middle ear of rabbits.Methods Five(10 ears)New Zealand rabbits were killed immediately after anaesthesia,the structures of tympanic membrane and tympanic cavity were observed by endoscopic transcanal approach,and ossicles,epitympanum,mesotympanum,hypotympanum and facial nerve were distinguished.Results Compared with human,auditory ossicles were composed of malleus-incus complex and stapes,and part of the lateral epitympanic wall was replaced by the tympanic membrane.Rabbit’s bullae was similar to the mesotympanum and hypotympanum of human,including the eustachian tube,facial nerve,promontory,vestibular window,cochlear window and tympanic nerve.The mastoid process was a diploic bone,overlying the caudolateral aspect of the tympanic bulla.In the tympanum,facial nerve run horizontally below the epitympanum,passed through the pyramidal eminence,and then run vertically along the posterior wall of bullae,and left the auditory vesicle through stylomastoid foramen.Conclusions The middle ear structures of New Zealand rabbits are similar to that of human,which can be used as the anatomical model for the junior otologists to practice endoscopic middle ear operation,or as a new educational model for the three-dimensional anatomical structure of the ear.