经颅多普勒超声评估Willis环动脉变异

目的探讨经颅多普勒超声评估Willis环动脉变异的价值。方法152例无脑血管病患者,在行颈总动脉压迫试验时采用经颅多普勒超声(TCD)检测大脑前动脉交通前段和大脑后动脉交通前段的血流速度。结果30%患者的前交通动脉和两侧后交通动脉均开放,构成一个血流动力学完整的Willis环;95%患者的Willis环前部动脉开放,另3%前交通动脉及2%大脑前动脉交通前段缺如导致Willis环前部动脉不开放;44%Willis环后部动脉发育异常,阻碍了侧支血流从基底动脉到颈内动脉.其中36%后交通动脉缺如.8%大脑后动脉起源于颈内动脉。结论经颅多普勒超声结合颈总动脉压迫试验检测Willis环动脉变异既安全又方便,其检出率与解剖学研究一致。

Artery variations in circle of Willis assessed by transcranial Doppler ultrasonography

Objective To assess the value of artery variations in circle of Willis with transeranial Doppler ultrasound. Methods In one hundred and fifty two patients without cerebrovaseular disease,the blood flow velocity changes in the precommunicating parts of anterior and posterior cerebral arteries were measured with transeranial Doppler during common carotid artery compression.Results In 30% of the patients,the anterior communicating artery and both posterior communicating artery were functionally patent,resulting in a hemedynamically complete circle of Willis.The anterior part of circle of Willis was functionally patent in 95% of the patients,failure of the pateney of anterior part of circle of Willis was caused by deletion of anterior communicating artery in 3% and deletion of precommunieating parts of anterior cerebral arteries in 2% of the patients.Anomalies in the posterior part of the circle of Willis were in 44% of the patients,hampering collateral flow from the basilar to the internal carotid artery.36% of posterior communicating arteries were absent and 8% of the posterior cerebral arteries originated from internal carotid artery.Conclusion Transcranial Doppler with common carotid artery compression is a safe and easy way to detect the artery variations in circle of Willis,with the same accuracy to anatomic studies.