颞下经前岩骨锁孔入路的显微解剖学研究

Microanatomical studies of the subtemporal anterior transpetrous keyhole approach

目的探讨颞下锁孔入路中前岩骨磨除范围、中上岩斜区显露的区域及手术技巧,为临床应用提供依据。方法对10具经10%甲醛固定的成人尸头标本模拟颞下经前岩骨锁孔入路,在显微镜下观察并测量显露的解剖结构。结果Kawase菱形区的面积为（248.2±12.4）mm^2,最大限度磨除前岩骨后的面积为（318.4±36.2）mm^2,两者比较有统计学意义。切开后颅窝硬膜,可以暴露上斜坡、内听道下方的部分中斜坡、基底动脉中部、脑桥下部、脑桥延髓沟、延髓上部、椎基底动脉交接部、椎动脉近端、小脑前下动脉脑桥前段和脑桥外侧段。磨除三叉神经压迹下方的骨质,可进一步暴露展神经、Dorello管孔、小脑前下动脉的起始点。结论颞下锁孔入路通过一个直径2.0-2.5cm的小骨窗,可以最大限度磨除前岩骨和暴露上、中斜坡。

Objective To investigate the extent of the anterior petrous bone removal, the upper and middle clivus exposure, and operational techniques in the subtemporal keyhole approach, which can be regard as the base of this approach in clinical use. Methods The subtemporal keyhole approach was imitated in ten adult cadaveric heads fixed in 10% formalin and perfused intracranial vessels with colored silicone. Under operative microscope, the anatomic structures were observed and important structures were measured after the anterior petrous bone removal. Results The area of Kawase rhomboid construct and the rhomboid-shaped construct was 248.2 ±12.4 mm^2 and 318.4 ±36.2 mm^2 , respectively. They have significant variability. After opening the posterior fossa dura, the window offerred an access to the upper clivus, the middle basilar artery the midclivus inferior to the internal acoustic canal, the middle basilar artery, the inferior portion of pons, pontomedullary junction, the upper portion of medullary pyramid, the vertebrobasilar junction, the upper segment of vertebral artery, the anterior pontine and lateral pontine segment of the anterior inferior cerebellar artery. Abducens nerve, Dorello＇canal, the origin of the anterior inferior eerebellar artery will be exposed after the removal of the petrous apex below the trigeminal impression. Conclusions It is feasible to maximally remove the anterior petrous bone and expose the upper and middle clivus through a craniecomy about 2 to 2. 5 cm.