松果体区脑池和蛛网膜的显微解剖研究

Microsurgical anatomy of cisterns and arachnoid membranes in pineal region

目的系统研究松果体区脑池及其蛛网膜结构的显微解剖学特点,为手术入路及手术操作提供解剖学依据。方法在手术显微镜下观察20例尸头松果体区各个脑池的形态、边界、内容物及相关蛛网膜结构。结果松果体区的蛛网膜结构包括蛛网膜袖套、环中脑后膜和小脑前中央膜,其中蛛网膜袖套由枕叶底、内侧面及小脑上表面蛛网膜在幕尖处汇合而成,包裹Galen静脉系统、松果体及松果体上隐窝;环中脑后膜由枕叶底面及小脑上表面蛛网膜在幕切迹处汇合形成,环绕并附着于中脑背侧;小脑前中央膜由小脑上表面蛛网膜和蛛网膜袖套汇合处发出,前下方附着于下丘。四叠体池与小脑上池通过小脑前中央膜分隔,与后胼周池通过蛛网膜袖套分隔,与环池后部通过环中脑后膜的升段分隔,环池后部与小脑中脑裂池通过环中脑后膜的水平段分隔。结论重新划分了松果体区各个脑池的范围与交通情况,明确了蛛网膜的形态与分布。

Objective To study micro-anatomical features of cisterns and their arachnoid membranes in pineal region. Methods Cisterns in pineal region including their shapes, borders, contents and arachnoidal membranes were observed in 20 cadaveric brains using an operating microscope. Results Arachnoid membranes of the pineal region include the arachnoidal envelope, the posterior perimesencephalic membrane and the cerebellar precentral membrane. At the level of the tentorial apex, arachnoid membranes covering the inferior-medial surface of occipital lobe and the superior surface of cerebellum converge to form the arachnoidal envelope, which encloses the vein of Galen with its tributaries, the pineal gland and the suprapineal recess. The posterior perimesencephalic membrane arises from the outer arachnoid membranes covering the inferior occipital lobe and the superior cerebellum at the tentorial edge. It surrounds and is attached to the dorsal mesencephalon. The cerebellar precentral membrane originates from the arachnoid membrane covering the superior cerebellum where it meets with the arachnoidal sleevelet, and is attached to the inferior colliculus anteroinferiorly. The quadrigeminal cistern borders the superior cerebellar cistern by the cerebellar precentral membrane, the posterior pericallosal cistern by the arachnoidal sleevelet and the posterior ambient cistern by the ascending part of the posterior perimesencephalic membrane; the posterior ambient cistern borders the cerebellomesencephalic cistern by the horizontal part of the posterior perimesencephalic membrane. Conclusion The borders, communications and relationships between cisterns in pineal region as well as their arachnoidmembranes were redefined in this study.