【作者】 张喜安；

【导师】 钟世镇； 漆松涛；

【作者基本信息】 中国人民解放军第一军医大学 ， 人体解剖学， 2003， 博士

【摘要】 目的 岩斜坡区病变位置深在，毗邻复杂的神经血管结构，外科手术治疗难度很大。此区显微外科手术最大的难点，是如何充分暴露病变和最大限度地减少手术相关并发症，这就需要神经外科医生熟知此区解剖特点，根据病变的范围、已出现的神经功能障碍、术前计划的切除程度等选择合理的手术入路。针对岩斜坡区病变的手术入路，主要分为外侧型和前方型入路，其中外侧型入路目前应用最广。为详细了解此区的解剖特点和外侧型手术入路的技术要点，我们对此区三个代表性颅底手术入路及其相关解剖进行了研究。 方法 应用福尔马林固定的成人头颅湿标本20例40侧，动脉系统20例均灌注红色乳胶，7例静脉系统灌注蓝色乳胶。本实验中岩斜坡区的定义为上下界自鞍背至枕骨大孔前缘，两侧界由上向下依次为Meckel氏窝、内听道口、颈静脉结节、枕骨髁。所选的三个具有代表性的入路分别为颞下经小脑幕经岩骨前部入路、乙状窦前经岩骨入路、枕下极外侧经枕骨髁入路。每一种入路研究10例20侧，其中颞下经岩骨前部切除入路和枕下外侧经枕骨髁入路共用同一标本，并对岩斜坡区相关解剖结构进行测量和拍摄，对测量数据进行统计学分析，对模拟手术操作中的心得体会进行总结。 结果 (1)在颞下经小脑幕经岩骨前部入路中，颧弓应切断以减少颞叶牵拉。Kawase菱形区的四个边分别为：岩大神经前内侧的三叉神经后缘、三叉神经压迹后缘至弓状隆起之间的岩骨嵴、弓状隆起及其延长线、岩大神经。内听道基本对应于岩浅大神经和弓状隆起夹角的等分线。以内听道口至岩大神经垂直线和内听道为界可将岩骨前部切除区分为前、中、后三个三角区，前三角内除外侧的颈内动脉外无重要结构，是向深部岩下窦方向磨除岩尖的主要三角区域，耳蜗在中三角内，后三角是否打开应根据内听道内结构是否受累决定。岩尖部磨除后，岩骨上面和内侧面的骨窗分别为2.6cm~2和1.9cm~2。此种入路暴露范围，可包括海绵窦、Meckel氏窝、内听道水平以上的上岩斜坡区和脑干腹侧面。(2)乙状窦前经岩骨入路可分为迷路后、部分迷路切除、经迷路、经耳蜗四种亚型。在开骨窗时，星点不能准确定位横窦乙状窦连接点，可采用乳突最第一军医大学博士研究生学位论文上点、颜线、乳突尖等定位乙状窦的走行。除了Labbe氏静脉，颜枕叶底面的引流静脉引流形式多样，应充分保护。岩骨内的内耳结构、面神经、颈静脉球解剖复杂，在不同的入路亚型中，根据需要暴露以利于最大限度改善暴露和保护重要结构。乙状窦前入路基本型迷路后入路暴露范围有限，并不能真正完全暴露岩尖内侧面和中斜坡，乙状窦前部分迷路切除入路已可完全暴露岩尖和中、上斜坡区，有与经迷路入路相似但略小的暴露范围，是非常好的入路。乙状窦前经迷路入路和经耳蜗入路尽管暴露中、上岩斜坡区非常好，术野也更浅，但不可避免的牺牲听力。(3)枕下极外侧经枕骨裸入路中，枕下外侧肌肉循层次分离，有助于暴露枕下三角及其内的椎动脉等结构，推动脉硬膜外段及硬膜内段及其分支与后组颅神经解剖关系复杂。以舌下神经脑池段为界，将枕骨大孔区硬膜内区域分为上、下两部，枕骨裸和颈静脉结节磨除分别影响这两部暴露。从对枕骨大孔区暴露角度来说，枕骨裸关节面的磨除局限于后113甚至更小暴露已达充分。枕骨裸磨除明显扩大了对枕骨大孔区下部，包括枕骨大孔前缘和Cl前方的直视范围，但其上方的枕骨大孔区上部，仍部分被颈静脉结节的隆起阻挡，颈静脉结节摘除后，不仅直视范围可达斜坡中下部，且颈静脉结节内侧面的硬膜死角变为可以直视。(4)岩斜坡区的后颅窝血管神经可分为上、中、下三个复合体，其毗邻和穿行关系多变。岩斜坡区硬膜血供主要来源于颈内动脉的脑膜垂体干和颈外动脉的咽升动脉。结论(1)本研究显示现代颅底手术入路尽管操作上耗时费力，但其暴露范围、术野深度、暴露角度等明显优于传统手术入路，是处理岩斜坡区病变必须掌握的入路。(2)由于此三种入路在操作中的多个步骤可能损伤重要结构，因此应根据手术暴露的需要，决定各重要结构是否应该暴露和切除，以最大限度满足手术需要和减少并发症。(3)岩斜坡区解剖复杂，具备系统的解剖知识和精巧的操作技巧才能熟练掌握现代颅底手术入路。更多还原

【Abstract】 Objective Surgical access to lesions of petroclival region represents a challenge , both because of the depth of the lesion site and the vicinity of complex neurovascular structures. Maximal exposure of the lesion with minimal approach-related complication is the most important problem to deal with in the microsurgery of these lesions. For this, accurate knowledge of the surgical anatomy of this region is mandatory, and the choice of type of approach is based on the location of lesion, preoperative neurological deficit, and extent of tumor removal in preoperative planning, etc. Surgical approach to petroclival region can be classified into anterior and lateral approach, the latter is widely used today. In order to understand the detailed anatomy of petroclival region and master the exquisite microsurgical skills in lateral approach, three representative skull-base approach and relative anatomy were studied.Methods Twenty formalin-fixed human adult cadaveric head (40 sides) were examined. Arteries were injected with red silicone in all heads and veins injected with blue silicone in 7. The definition of petroclival region used in this study is as follows: The petroclival region is the area between dorsum sellae and anterior border of foramen magenum which is medial to, anterosuperiorly to posteroinferiorly, the Meckel’s cave, internal auditory foramen, jugular tubercle, and occipital condylar. The approaches studied were subtemporal transtentorial anteiror transpetrosal approach, suboccipital extreme lateral transcondylar approach, and presigmoid transpetrosal approach. 10 heads (20 sides) were used in each approach, the former two approach were studied in the same 10 heads, and the petroclival structures are measured and filmed. The data was statistically analyzed. My personal experience in dissection was summarized.Results (1) In subtemporal transtentorial anterior transpetrosal approach, the zygomatic arch should be removed to minimize the temperal lobe retraction. Therhomboid area of Kawase is bordered anteromedially by posterior border of trigeminal nerve, posteromedially by petrous ridge, posterolaterally by arcuate prominence (AP), anterolaterally by great superficial petrosal nerve (GSPN). The internal auditory canal is corresponding to the bisectrix of triangle formed by AP and GSPN. A line through the internal auditory foramen that is perpendicular to the GSPN and the internal auditory canal divided the rhomboid Kawase area into three triangle. Except for the internal carotid artery in its lateral border, there is no important structure in the anterior triangle which is the main area to drill the petrous apex. The cochlea is located in the depth of middle triangle. Whether the bone in the posterior triangle should be drilled depend on fact whether the internal auditory canal is involved. After pectrosectomy, the size of the windows in the superior and medial surfaces of petrous bone averaged 2.6cm2 and 1.9cm2, respectively. The exposure of this approach include cavernous sinus, Meckel’s cave, the upper petroclival region and ventral surface of brain stem above the level of internal auditory canal. (2) The presigmoid transpetrosal approach have four subtypes including retrolabyrinth, partial labyrinthectomy, translabyrinth, transcochlear approaches. During the craniotomy, the anion can not precisely predict the junction of transverse-sigmoid sinus. The most superior mastoid point, temporal line, and mastoid tip can be used to locate the sigmoid sinus. Except for the well-known vein of Labbe, the bridging vein of basal temporal and occipital lobe vary and need to be protected as much as possible. The structures in petrous bone including inner ear structures, facial nerve, jugular glomus have a complex anatomical relationship, so that they should be adequately exposed as needed in different subtypes of presigmoid approach. The basic subtype of presigmoid transpetrosal approach has a limited exposure which can not truly expose the inner surface of petrous apex and middle clivus. The partial labyrint更多还原