颅内动脉瘤内血流速度与瘤腔大小的相关性

The correlation between blood flow velocity in intracranial aneurysm cavity and the size of aneurysm

目的探讨颅内动脉瘤大小与瘤腔和载瘤动脉内血流速度的相关性。方法将15个颅内动脉瘤的数字减影血管造影(DSA)影像学资料存入计算机内,用图像处理软件测出图像中选定区域像素随时间变化的密度值,并绘成时间-密度曲线,从曲线方程中求出曲线的流入系数Ka值并进行统计分析,以了解不同大小动脉瘤腔内的血流速度。结果标志瘤腔内血流速度的动脉瘤中心区域Ka值(ACKa值)与动脉瘤大小呈负相关,r=-0．521,P=0．046(双侧)。动脉瘤大小与载瘤动脉内标志血流速度的Ka值(PKa值)无相关性,r=0．107,P=0．704(双侧)。结论动脉瘤腔越大,动脉瘤中心部位的血流越慢；动脉瘤腔越小,血流速度衰减越少,瘤腔中心区的血流速度越快。而载瘤动脉内的血流速度与动脉瘤大小无关。这一结果可用于评估动脉瘤的自然转归、栓塞治疗效果,并能对动脉瘤的复发原因做出部分解释。

Objective To explore the correlation of the size of intracranial aneurysms with the blood flow velocity in the aneurysmal cavity and the parent artery. Methods The video data of serial digital subtraction angiography （DSA） images of 15 intracranial aneurysms in 15 patients were copied to a personal computer, then the pixel density values in the selected areas of images were measured with the changes of time by an image processing software, and the time-density curves were generated. The inflow coefficient Ka values of the curve were calculated by curve equation and the statistical analysis was performed so as to find out the blood flow velocity in various aneurismal cavities. Results The Ka value that marked the blood flow velocity in aneurismal cavity （ACKa） in the central area of an aneurism had a negative correlation with the size of the aneurysm, r = - 0. 521, P = 0. 046 （ both sides）. The size of the aneurysm had no correlation with the Ka value of the marked blood flow velocity in a parent artery （PKa）, r =0. 107, P = 0. 704 （ both sides）. Conclusion The larger the aneurismal cavity, the slower the blood flow velocity in the central area of the aneurysm. The smaller the aneurysmal cavity, the fewer attenuation of blood flow velocity in the aneurysms, and the faster the blood flow velocity in the central area of the aneurysm. However, the flow velocity in parent artery is not associated with the size of aneurysm. The results of the study can be used to evaluate the natural outcome of aneurysm, the efficacy of embolization, and may partly explain the causes of aneurismal recurrence.