眶颧额颞下入路对Willis 动脉环的显微解剖

目的 对Willis动脉环及其穿支进行解剖观察与测量，为临床手术提供依据。方法 在手术显微镜下对5例成人尸体头颅经眶颧额颞下入路对动脉环进行显微解剖研究。结果 Willis动脉环由前交通动脉，左右大脑前动脉A1段，左右颈内动脉，左右后交通动脉及在右大脑后动脉内侧段组成，Willis动脉环变异多，尤其以大脑前动脉A1段明显，且左侧A1外径大于右侧A1外径。脑底动脉环上各部均有穿支发出，一般从起源动脉发出后走向内上方分布到垂体柄，视束，视交叉，丘脑，下丘脑，基底节和内囊等区域供血。结论 熟悉Willis动脉环的显微解剖，保护好其穿支是获得良好的手术效果的关键。

Observation on Microsurgery of the Willis Circle by Combined Frontotemporal-Orbitozygomatic Approach

Objective To get more detailed information about the microsurgery of the Willis circle,in order to provide evidence of clinical operation.Methods The microsurgical anatomy of the Willis circle via combined frontotemporal-orbitozygomatic approach was studied in 5 adult cadaver brains under microsurgical scope. Results The Willis circle was composed of anterior communicating artery (ACOA), A 1 segments of the right and left anterior cerebral arteries (ACA), right and left internal carotid arteries(ICA) right and left, posterior communicating artery (PCOA), Pi segments of the right and left posterior cerebral arteries (PCA).The variation are present obviously in A 1 segment of the ACA. The outer diameter of left A 1 segment are larger than that of right ones. There are many perforating arteries of each part of Willis circle. Most of them arise from their original arteries, then course medial-superiorly to the optic tract, the pituitary stalk, the optic chiasm, the thalamus, hypothalamus, the floor of third ventricle, basal nuclei and internal capsule etc blood supplied areas. Conclusion To understand the microsurgical anotamy of the Willis circle and protections against its penetrating branches perfectly are the key to gain a good curative effect during the concerned operation .