氙-CT动态观察动脉瘤性蛛网膜下腔出血患者脑血流量变化的初步研究

Dynamic observation of changes of cerebral blood flow in patients with aneurysmal subarachnoid hemorrhage with xenon-CT:a preliminary study

目的探讨应用氙(Xe)-CT评价动脉瘤性蛛网膜下腔出血(SAH)患者的脑血流量变化以及与经颅多普勒超声(TCD)检测脑血流速度的关系。方法对7例在SAH后1～4d和7～14d的颅内动脉瘤患者进行2次Xe-CT检查。用自动皮质6分区模式和手工画法测量大脑中动脉(MCA)等血管分布区(每例患者双侧大脑半球10个感兴趣区,7例患者共70个)的脑血流量。在Xe-CT检查后1h内,采用TCD检测MCA血流速度,比较MCA供血区脑血流量与TCD检测的血流速度的相关性。结果Xe-CT检测7例患者SAH后1～4d双侧MCA供血区平均脑血流量为(48±12)ml.100g-1.min-1,7～14d为(43±15)ml.100g-1.min-1,TCD检测SAH后1～4d双侧MCA平均流速为(165±73)cm/s,7～14d为(151±70)cm/s。Xe-CT检测的MCA供血区局部脑血流量与TCD检测的MCA血流速度比较,SAH后1～4d的左侧MCA的脑血流量与血流速度呈显著正相关(r=0.869,P<0.05),SAH后1～4d的右侧MCA和7～14d的双侧MCA的脑血流量和血流速度均呈负相关,但差异均无统计学意义(P>0.05)。结论Xe-CT能获得脑血流量绝对值,可用于动脉瘤性SAH患者的脑血流量评价。TCD检测的MCA流速与Xe-CT测得的局部脑血流量可能无明显相关性,有待于扩大样本,继续深入研究。

Objective To investigate the relationship between the evaluation of the changes of cerebral blood flow with xenon （Xe） -CT and the measurement of cerebral blood flow velocity with transcranial Doppler （TCD） in patients with aneurysmal subarachnoid hemorrhage （SAH）. Methods Two Xe-CT examinations were performed in 7 patients on day 1 to 4 and 7 to 14 after SAH. The cerebral blood flow in vascularity areas （ 10 interest regions in bilateral hemisphere in each patient） of the middle cerebral artery （MCA） was measured by the 6 automatic cortex mapping pattern and manual mapping method. The blood flow velocity of MCA was detected by transcranial Doppler （TCD） within one hour after Xe-CT examination. The correlation between the cerebral blood flow in the territory of MCA and the blood flow velocity detected by TCD was compared. Results The average cerebral blood flow in the bilateral MCA territories in 7 patients examined by Xe-CT after SAH was 48 ± 12 ml·100g^-1·min^-1 on day 1 to 4, and 43 ± 15 ml·100 g^-1 ·min^-1 on day 7 to 14. The average blood flow velocity of the bilateral MCA measured by TCD on day l to 4 after SAH was 165 ± 73 cm/s, and it was 151 ± 70 cm/s on day 7 to 14. The regional cerebral blood flow in the territories of MCA detected by Xe-CT compared with the blood flow velocity of MCA measured by TCD, and the cerebral blood flow of the left MCA was significantly positively correlated with the blood flow velocity on day 1 to 4 after SAH （ r = 0. 867, P 〈 0. 05）. Both the cerebral blood flow of the fight MCA on day 1 to 4 and the bilateral MCA on day 7 to 14 after SAH were significantly negatively correlated with the blood flow velocity, but there was no statistical significance （P 〉 0. 05 ）. Conclusion Xe-CT can get the absolute value of cerebral blood flow. It can be used in evaluation of cerebral blood flow in patient with aneurysmal SAH. The blood flow velocity of MCA measured by TCD have no obvious correlation with the cerebral blood flow detected by Xe-CT.