人脑Willis动脉环前循环变异的显微解剖

Microsurgical anatomic variations in anterior portion of arterial circle of Willis

目的探讨Willis动脉环前半环各组成血管的解剖变异特点。方法利用45具(90侧)福尔马林固定的硬脑膜完整的成人脑标本进行Willis动脉环前半环各血管显微解剖,观察和测量血管的形态和走行。结果约13.3%的标本大脑前动脉双侧A1段发育不均衡,约6.7%交叉对侧供应;前交通动脉简单型仅占37.8%,复杂型占60%。结论约60%以上的人脑Willis动脉环前半环存在变异,熟悉这一区域的变异对介入治疗和手术有很大意义。

Objective To study the anatomic variations in anterior portion of arterial circle of Willis. Methods The microsurgical anatomy of the anterior portion of the arterial circle of Willis in 45 cases （90 sides） of adult cadaver heads fixed in formalin was observed under microscope. The configuration and pathway of vessels were obtained. Results A difference in diameter between the left and fight A1 segments was found in 13.3% of cerebral hemispheres in the brain specimens. The A2 segments of both hemispheres were derived from contralateral A1 segments in 6.7% of the specimens. Simple type of anterior communicating artery was encountered in only 37.8% of the specimens and complex type in 60%. Conclusion Variations in anterior portion of arterial circle of Willis exist in approximately 60% of human brains. A better understanding of the anatomic variations may do great help to the interventional therapy.