颞底-经小脑幕手术入路的应用解剖学

Applied anatomical study of posterior subtemporal transtentorial approach

目的 :对后颞部进行解剖学研究 ,为颞底 -经小脑幕手术入路提供解剖学基础。方法 :采用干性颅骨标本 2 0例及福尔马林固定的头颅标本 15例 ,进行解剖研究和模拟颞底 -经小脑幕入路。结果 :横窦从窦汇处开始向前逐渐升高 ,在顶乳突缝前角处 ,呈弧形向外移行于乙状窦 ,上缘与颧弓延长线的距离为 (11.2± 2 .2 )mm (8.2～ 14 .5mm )。顶乳突缝前角、星点与STP距离分别是 (2 .1± 2 .6)mm (0～ 9.3mm) ;(2 0 .4± 4.0 )mm(14 .1～ 2 6.4mm )。星点位于横窦上缘上、横窦上 1/2、横窦下 1/2、横窦下缘下分别占 16.7%、2 6.7%、3 3 .3 %、2 3 .3 %。颧弓、乳突上嵴与其相对应的颅中窝底相平。结论 :颞底 -经小脑幕入路骨窗的关键孔 (孔 1) :圆心在乳突上嵴 ,孔后缘与顶乳突缝前角相切。孔 2 :于关键孔后方 ,下缘与颧弓延长线的距离为 15mm。孔 3 :于关键孔前方 ,下缘平颧弓。星点变异大 ,不易作为定位横窦的标志。

Objective: To study the relationship of anatomical landmarks of posterior temporal cranial base and gain the orientation for posterior subtemporal transtentorial approach. Methods: Twenty dried skulls and fifteen injected adult cadaver specimens were used to study morphometric relationships on both sides of each specimen and simulate the operation process of posterior subtemporal transtentorial approach. Results: The distance between the superior line of the transverse sinus and the extended line of the zygoma arch was (11.2±2.2)mm(8.2～14.5 mm). The gaps from STP to the angle of parietomastoid sutures and to the asterion were (2.1±2.6)mm(0～9.3 mm)and (20.4±4.0)mm (14.1～26.4 mm)respectively. The location of the asterion was above upper rim of the transverse sinus in 16.7%, superior half of the transverse sinus in 26.7%, inferior half of the transverse sinus in 33.3%, below lower rim of the transverse sinus in 23.3%.The anterior angle of parietomastoid sutures lay over the junction of the transverse sinus and the sigmoid sinus. The anterior portion of the supramastoid crest and zygoma root correlated with the level of the middle fossa. Conclusion: The asterion is variable and limits its usefulness as a consistently stable marker. The keyhole of posterior subtemporal transtentorial approach locates on the supramastoid crest with the posterior rim on anterior angle of parietomastoid sutures. The second hole is posterior to the first with the inferior rim 15 mm above the extended line of the zygoma arch. The third hole is anterior to the first with the inferior rim on the level of zygoma arch.