应用经颅多普勒超声对颅内动静脉畸形盗血程度进行量化评估

目的 通过对盗血现象的分析,完善颅内动静脉畸形(AVM)的经颅多普勒超声(TCD)诊断,并应用盗血指数(SI),评估AVM的盗血程度。 方法 应用AVM非供血动脉血流的低流速、高阻力特点,进行逆向推导的逆向诊断法;并对16例经脑血管造影数字减影(DSA)证实的颅内AVM的TCD资料进行回顺性分析。以供血动脉及其相邻非供血动脉的Vm供／Vm邻比值和相应的SI值进行相关分析,并尝试比较SI与AVM大小的关系。 结果 通过逆向诊断将Vm供／Vm邻比值,同相应SI值进行相关分析,r=0.66,p=0.000,n=42;SI与动静脉畸形大小呈正相关趋势(r=0.48,n=12),p>0.05,无显著意义,SI大小可能与AVM的类型、大小和血管发育程度等有关。 结论 AVM的盗血现象应作为TCD重要的诊断条件之一,分析TCD的SI值大小,结合DSA检测结果,可以对AVM的类型、血管床的发育情况和大小进行分析判定。

Evaluation of steal phenomena of intracranial arteriovenous malformation by means of transcranial doppler ultrasonography

Objective Improve the diagnosis method of intracranial arteriovenous malformation(AVM) with transcranial doppler by means of analysis of steal phenomena of cerebrovascular blood flow in areas of AVM. Evaluate the steal phenomena of AVM with steal index (SI). Methods Introduce a method of eon-verse diagnosis that applied the character of low velocity and high resistance of the arteries near AVMs. The data of 16 cases of AVM, which were both diagnosed by DSA and TCD, were analyzed retrospectively. Take the ratio of the mean blood velocity of feeding vessels (Vmfv) that provide blood for the area of AVM and the mean blood velocity of neighbour artery (Vmna) , Vmfv/Vmna, compared with corresponding SI, the correlation between the ratio and the SI was analyzed. The correlation between the sizes of AVMs and the values of SI was also analyzed by statistics. Results There is positive correlation between the Vmfv/Vmna ratio and corresponding SI, r = 0. 66, P<0. 001, n =42. The relationship between the sizes of AVM and corresponding SI has positive correlation trend, but is insignificant (r = 0. 48, P>0. 05, n = 12, ). Conclusion SI of AVM should be emphasized in the diagnosis of AVM with TCD. The type, size and vascular development of AVM can be evaluated by analyzing the value of SI together with DSA images.