乳突手术中面神经易损伤区的显微解剖

Microanatomical study of the area in which the facial nerve being easy to damage in mastoid surgery

目的研究有关乳突手术中的面神经易损伤区的显微解剖，为临床应用提供解剖学资料。方法通过模拟临床乳突手术方法，解剖20个成人湿头颅标本（40侧颞骨），显露并观测易损伤区内的面神经水平段、垂直段、锥曲段及其毗邻结构。结果面神经水平段的长度为（8．85±1．01）mm（7．10～11．25mm）；直径为（1．88±0．65）mm（1．55～1．90mm）；水平段与垂直段的夹角（向前）为（115．50±6．89°）（109．5°～128．6°）；匙突到该段的垂直距离为（1．89±0．58）mm（0．90～3．05mm）；镫骨足板中点到该段的垂直距离为（1．92±0．52）mm（1．44～2．56mm）；镫骨头到该段的垂直距离为（2．30±0．85）mm（1．97～3．11mm）；水平段与鼓室天盖夹角（向后）为（28．5°±3．66°）（25．8°～31．5°）；锥曲段的直径为（1．89±0．65）mm（1．56～1．88mm）；锥曲段顶点到砧骨短脚尖的距离为（2．55±0．21）mm（2．10～2．90mm）；到外半规管隆突的距离为（2．86±0．31）mm（2．23～3．56mm）；面神经垂直段近段的直径为（2．13±0．13）mm（1．90～2．40mm）；鼓索与面神经垂直段的夹角（向上）为（38．60±1．99°）（28．5°～52．5°）；锥隆起尖到面神经垂直段的垂直距离为（2．05±0．65）mm（1．85～2．36mm）。结论面神经易损伤区内的外半规管（水平半规管）隆突、砧骨短脚、匙突、鼓室天盖、镫骨、锥隆起、鼓索是乳突手术中的重要标志．其结构空间位置关系复杂，手术操作必须在熟悉显微解剖学知识的基础上进行。

Objective To study the microanatomy of the area in which the facial nerve being easy to damage in mastoid surgery, in order to provide microanatomical datas for the clinical works. Methods In 20 adult wet skull specimens （40 temporal bones）, the segments of facial nerve and their adjacent structures in the area in which the facial nerve being easy to damage were observed according to operation of mastoid surgery. Results The length of the horizontal segment was （8.85±1.01） mm （7.10-11.25 mm）, the diameter was （1.88 ± 0.65） mm （1.55-1.90 mm）; The angle opening towards anterior direction between horizontal segment and vertical segment was （115.5° ± 6.89°） （109.5-128.6°）; The vertical distance from the cochlearform process to this segment was （1.89 ± 0.58） mm （0.90-3.05 mm）; The vertical distance from the midpoint of the base of stapes to this segment was （1.92 ± 0.52） mm （1.4±2.56 mm）; The vertical distance from the head of the stapes to this segment was （2.30 ± 0.85） mm （1.97-3.11 mm）; The angle towards posterior direction between horizontal segment of facial nerve and tympanic tegmen was （28.5° ± 3.66°） （25.8°-31.5°）; The diameter of the pyramidal segment of facial nerve was （1.89 ± 0.65） mm （1.56-1.88 mm） ; The distance between the su mmit of pyramidal segment of facial nerve and the apex of shor limb of incus was （2.55 ± 0.21） mm （2.10-2.90 mm）; The distance from the summit to the eminence of the lateral semicircular canal was （2.86 ±0.31） mm （2.23-3.56 mm）; The diameter of the proximal part of vertical segment of facial nerve was （2.13 ± 0.13） mm （1.90-2.40 mm）; The angle towards superior direction between verical segment of facial nerve and chorda tympani nerve was （38.60 ± 1.99°） （28.5°-52.5°）; The vertical distance from the top of the pyramidal eminence to the vertical segment of the facial nerve was （2.05 ± 0.65） mm （1.85-2.36 mm）. Coneluslons The eminence of the lateral semicircular canal, short limb of incus, cochlearform process, tympanic tegmen, stapes, pyramidal eminence, chorda tympani nerve in the area are important landmarks to be located in mastoid surgery. The anatomic relations in this area are complicated and compact. Anatomical knowledge is very important to the surgery of this area.