颞底经小脑幕经岩入路的解剖研究

目的 探讨颞底经小脑幕经岩入路(TBTTA)中岩骨可以磨除的区域,及该入路对岩斜区结构暴露的情况.方法 应用成人湿头颅标本10例(20侧),模拟TBTTA人路,界定岩骨可以磨除的范围,并比较岩骨磨除前后岩斜区结构暴露情况及对颞底所需牵拉的程度.结果 以内听道为中心分中间部、内侧部、外侧部来磨除岩骨.岩骨可磨除范围:中间部宽度6.6 mm,长度在内听道口为5 mm,在内听道底约为2 mm;内侧部长度可为15 mm,宽度为9 mm;外侧部在内听道和上半规管之间区域中,长度为8.7 mm,宽度为5 mm,右半规管区域磨除深度不能超过3.7 mm.通过磨除适当范围的岩骨,TBTTA入路可以明显改善岩斜区结构的暴露;颞底牵拉程度明显减少.结论 不磨除岩骨的单纯颞底经小脑幕入路中,对岩骨后颅窝面的观察仍然受到岩嵴的阻挡;而TRTTA入路从硬膜下磨除适度范围的岩骨,可以明显改善对岩骨后颅窝面及邻近结构的暴露,减少对颞底的牵拉并无需进行特殊的颅底重建.

Applied anatomical study of the temporal base transtentorial transpetrosal approach

Objective To explore the resecting region of the petrosal bone and the extended exposed area in temporal base transpetrosal transtentorial approach(TBTTA).Method Ten adult cadaver heads for a total of 20 sides were performed by TBTTA and the resecting region of the petrosal bone was identified in this approach.The exposure at petroclivus and the angle of temporal base retraction was evaluated in TBTTA approach.Results The petrosal bone can be divided into three parties by the internal acoustic canal.In the medial part,the drilling area was 6.6 mm wide and 5 mm long above the internal acoustic foramen(2 mm long above the bottom of internal acoustic canal).In the intermediate part,the safe drilling area was 15 mm long and 9 mm wide.In the lateral part,the resecting area between the internal auditory canal and semicircular canals was 8.7 mm long and 5 mm wide:and in the area of semicircular canals,the drilling deep should be restricted within 3.7 mm.After resecting the petrosal bone which block the visual of the most part of the pefrosal posterior wall,the exposed area was obviously enlarged,and the temporal base retracting angle reduced.Conclusions TBTTA approach can significantly improve the visual field in the petroclival region and reduce the degree of the temporal base retraction by resecting petrosal ridge.