Willis环变异和血流动力学改变对颅内单发动脉瘤形成的影响

Effects of circle of Willis variation and hemodynamic alteration on formation of single intracranialaneurysm

目的分析颅内动脉瘤（IA）患者的Willis环变异和血流动力学改变，并探讨影响IA单发的临床因素。方法回顾性纳入2010年11月至2011年11月南方医科大学珠江医院神经外科收治的经数字减影血管造影（DSA）确诊的223例单发IA患者（IA组），同时纳入同期DSA检查为阴性者为对照组（118例）。所有患者均行三维DSA（3D—DSA）检查，并对图像进行三维重建，以判断Willis环变异类型；采用经颅彩色双功超声（TCCD）检查获取颅内血流动力学相关参数。进一步采用单因素和多因素logistic回归方法分析影响IA单发的危险因素。结果IA组患者的Willis环变异率显著高于对照组[分别为78．0％（174／223）、11．9％（14／118），P〈0．001]。IA组患者的Willis前环变异率高于后环[分别为63．8％（111／174）、36．2％（63／174）]，且Willis前环变异更多见于左侧[左、右侧分别为46．O％（80／174）、17．8％（31／174）]。IA组患者的切应力（WSS）和环壁张力（CWT）均显著高于对照组[WSS分别为（8．74-2．7）dyne／cm2、（7．9±1．6）dyn·Jcm2，P=0．007；CWT分别为（3．84-1．1）dyne／cm2、（3．5±1．0）dyne／cm2，P：0．014]。单因素和多因素logistic回归分析结果显示，女性（OR=1．970，95％C1：1．010-3．870，P=0．048）、高血压Ⅱ级（OR=2．830，95％CI：1．160-86．880，P：0．022）、Willis环变异（OR=29．680，95％ CI：10．280—85．680，P〈0．001）和WSS增高（0R=1．530，95％ CI：1．140-2．070，P=0．005）是影响IA单发的独立危险因素。结论Willis环变异好发于IA患者，且左侧的Willis前环变异更多见。女性、高血压Ⅱ级、Willis环变异和血流动力学改变是影响IA单发的危险因素。

Objective To evaluate the tendency of circle of Willis variation and hemodynamic alteration for the purpose of identifying predictors of single intracranial aneurysnl （IA） formation. Methods A retrospective study was conducted on 223 patients with DSA-confirmed single IA （ IA group） admitted to Neurosurgery Department of Zhujiang Hospital, Southern Medical Hospital and 118 patients without IA （control group） from November 2010 to November 2011. The 3D-DSA images were carefully evaluated to confirm the variation of circle of Willis by vascular structural abnormity in those 2 groups. TCCD （ transcranial color Doppler） was performed to measure the hemodynamic parameters. Multivariate predictors of IA formation were analyzed by using univariate analysis and multivariate logistic regression. Results The incidence of variation of circle of Willis in IA group was higher than that in control group [ 78.0% （174/223） vs. 11.9% （ 14/118）, P 〈 0. 001 ]. Besides, the incidence of variation of anterior circle of Willis in IA group was higher than that of variation of posterior circle of Willis [63.8% （111/174） vs. 36.2% （63/174）]. The incidence of variation of anterior circle of Willis in IA group was more in the leftside than the right [46.0% （80/174） vs. 17.8% （31/174） 1. Both WSS （arterial wall shear stress） and CWT （ eircumferential wall tension） in IA group were higher than those in control group （ WSS ： 8.7 ±2.7 dyne/era2vs. 7.9±1.6 dyne/cm2, P=0.007; CWT： 3.8＋1.1 dyne/erae vs. 3.5±1.0 dyne/cm2, P=0. 014I. Univariate and multivariate analysis showed that the female gender （OR = 1. 970, 95% CI： 1.010-3.870, P=0.048）, hypertension （grade ]I） （OR=2.830, 95%CI：1. 160-86.880, P= 0. 022） , variation of eirele of Willis （ OR = 29. 680, 95% CI： 10. 280 - 85. 680, P 〈 0. 001 ） and WSS （ OR = 1. 530, 95% CI： 1. 140 - 2. 070, P = 0. 005 ） were independent risk factors of IA formation. Conclusions The variation of circle of Willis predominantly oecurs in IA patient. The ineidenee rate of variation of anterior eirele of Willis seems higher than that of variation of posterior eirele of Willis. The female gender, hypertension （ grade II ） , variation of eirele of Willis and WSS are independent risk factors of IA formation.