【作者】 刘亮；

【导师】 冯忠堂；

【作者基本信息】 昆明医学院 ， 神经外科学， 2004， 硕士

【摘要】 [目的]：探讨后颅窝远外侧手术入路的显微外科解剖 [方法]：在30个(60侧)干颅骨上对枕大孔区的重要骨性结构(枕骨大孔、枕髁、舌下神经管等)的形状、大小及毗邻结构进行测量。在10个(20侧)10％福尔马林固定的成人连颈尸体头颅标本上进行模拟远外侧手术入路进行解剖，显露枕下区的椎动脉，测量相关参数。行枕下颅骨切除，切开硬膜，显露脑干腹侧及腹外侧结构，观察椎动脉第四段与后组颅神经的毗邻关系。在手术显微镜下(×4～10)对15个(30侧)10％福尔马林固定的成人尸头标本进行解剖，显露枕髁关节面，自后外向前内方向磨除枕髁，记录显露舌下神经管内口所磨除的枕髁量。于枕外隆凸尖上方6cm处沿水平面锯开颅骨，去除颅盖和大脑，保留脑干、小脑，观测颅内椎动脉第四段(V4)的管径、走行、分支，观察并测量后组颅神经的起源部位、神经束组成，测量延髓腹侧及下斜坡相关结构的参数。 [结果]：1．枕髁位于枕骨大孔两侧，舌下神经管位于枕髁中后1／3处，磨除枕髁至舌下神经管内口处，可较好地显露枕大孔区腹侧结构。2．第二颈神经根的前支均从椎动脉寰枢椎段的背侧越过，椎动脉颅外段长度及弯曲变异较大，外周有静脉丛或静脉窦包裹。3．椎动脉颅内段绝大多数走行于后组颅神经的腹侧，小脑后下动脉起自椎动脉，并在后组颅神经之间穿行。4．从椎动脉前方切开硬膜，可避开在后组颅神经根丝间的操作，减少对脑干的牵拉。5．后组颅神经与下橄榄关系密切。 [结论]1．寰椎横突是辨认椎动脉的重要标志。2．舌下神经管周围的皮质骨可作为抵达舌下神经管的标志，并可估计枕髁切除的范围。3．研究后颅窝远外侧入路的显微解剖，有助于切除枕大孔腹侧及下斜坡区的肿瘤，保护重要结构。更多还原

【Abstract】 Objective: The purpose of this study is to observe microsurgical anatomy of far lateral approach of posterior cranial fossa.Methods: 30(60 sides)adult dried skulls ,10(20 sides)adult cadaveric heads with connected neck fixed with 10% formalin,and another 15(30 sides) adult cadaveric heads were examined in this study .The important structures such as the foramen magnum,occipital condyle,hypoglossal canal were investigated on the dried skulls. The suboccipital segment of vertebral artery was dissected and measured on the cadaveric heads with connected neck according to the procedures of far lateral approach. The ventro-and ventrolateral brain stem was exposed after removing suboccipital skull and splitting dural.The relationship among the forth segment of the vertebral artery and the low cranial nerves was observed. The occipital condylewas drilled to the intracranial end of the hypoglossal canal from posterior lateral margin according to the procedures of far lateral approach under the surgical microscope(X4~10 magnification).Then the drilled length was measured . The skull was sawed off at the level of 6cm above the external occipital protuberance. The calvarium and cerebrum were removed. The brain stem and cerebella were reserved .Then the forth segment of the vertebral artery, the low cranial nerves and the structures of the ventro- marrow and the lower clival were observed and measured. Result:1. The occipital condyle was located at lateral side of the foramen magnum, the intracranial end of the hypoglossal canal was located above the junction of the posterior and middle one-third of the occipital condyle.The structures of ventro- foramen magnum region were exposed preferably when the occipital condyle was drilled to the the intracranial end of the hypoglossal canal. 2 The former branch of C2 nerve all crossed from the back of the suboccipital segment ofvertebral artery which was enclosed by either venous plexus or venous sinus and its length andcurve were various significantly.3.The encephalic segment of the vertebral artery tracked mostly in the front of the low cranialnerves.The posterior inferior cerebrellar artery send out from the vertebral artery and acrossedbetween the root of the low cranial nerves.4.Dural opened from front of the vertebral artery may avoid operation among the low cranialnerves and reduce the pull of brain stem.5. The olive had an intimacy relationship with the low cranial nerves.Conclusions:.The transverse process of the atlas was the important landmark foridentification of the vertebral artery.2.The cortex arounding the intracranial end of the hypoglossal canal can be seen as the landmarkfor arrival of the hypoglossal canal and estimate the resected extension of the occipital condyle.3.Study of microanatomy in the far lateral approach is helpful of resecting tumours of theventro- foramen magnum and the lower clival region and preserving important tissues.更多还原