人脑Willis动脉环后循环变异的显微解剖研究

Microsurgical anatomy of variations of posterior portion in arterial circle of Willis

目的了解人脑Willis动脉环后循环的变异特点,为血管和颅底外科手术提供参考依据。方法对46例经福尔马林处理的人脑完整标本在显微镜下进行观察、测算,并作摄影。结果46例(92侧)中,两侧后交通动脉(PCoA)管径不等超过60%,长度相差2mm以上者约占50%;PCoA与大脑后动脉(PCA)的解剖关系中,约50%发育正常;基底动脉(BA)与两侧PCA组成的分叉角为45°～150°,平均105°,PCA交通前段内穿支出现率98%。结论人脑Willis动脉环后循环中,约50%以上存在血管的管径、长度和解剖变异。

Objective To study the variations of posterior portion in arterial circle of Willis and provide references for vascular and cranial base surgery. Methods A total of 46 cases of adult cadaver heads fixed by formalin were dissected, observed, measured and photographed under microscope. Results Over 60% of posterior commnunieating artery （PCoA） in 46 cases （92 sides） owned unequal diameter between two sides. About 50% of the cases showed the variation of more than 2 mm in length. Approximately 50% of anatomic relations between PCoA and posterior cerebral artery （PCA） developed normally. Basilar artery （BA） was at an average angle of 105° （45°- 150°） with bilateral PCA. The occurrence rate of perforating branches from the precommunicating segment was 98%. Conclusion More than 50% of cases possess the variations in diameter, length and anatomy of vessels in the posterior part of Willis＇circle .