Dynamic Changes of Willis Circle by Manual Compression of the Proximal Common Carotid Artery During CT Angiography

Objective To investigate whether the dysplasia of Willis circle is variable by manual compression of the proximal common carotid artery( CCA) during CT angiography( CTA). Methods 100 healthy volunteers( 52 male,48 female) without carotid artery stenosis were investigated. CTA was performed during the resting and oppression carotid artery. Variables including the integrity type of circle of Willis,blocked and open segment vascular redistribution of anterior and posterior circulation were analyzed by 2 test. The differences of the diameter including ACo A and carotid ipsilateral vessel( ACA- A1,PCA- P1,PCOA,ACo A) were analyzed by t tests. Results The differences of two states in the integrity type of circle of Willis,blocked and open segment vascular redistribution of anterior and posterior circulation were statistically significant( χ2= 17. 007,88. 658,23. 990,P = 0. 000,0. 000,0. 000 0. 050). There was significant difference in the diameter of the ACo A and ACA- Al,but there was no statistically significant difference between diameter of the PCOA and PCA- P1. Conclusion Manual compression of the proximal common carotid artery( CCA) can lead to the circle of Willis morphological changes,multi- slice spiral CT angiography( CTA) combined with the test can be used to display individual primary collateral circulation and cerebral vascular reserve function,and timely detected sub- health population.