The Research on Hemodynamics in the Intracranial A-V Shunt Model

脑动静脉畸形（AVM）的血流动力学研究仍存在争议，AVM的实验模型尚未建立。我们建立了一种表现为局灶性低灌注的颅内动静脉分流动物模型，在大脑中动脉（MCA）皮质分支与上级矢状窦（SSS）之间端侧吻合股静脉移植物，在此模型上，记录了在吻合的MCA区域打开分流前后CBF的变化，以及双侧大脑前动脉（ACA）区域。此外，用5%的氧饱和度检测分流前后脑血管的CO2反应性MCA区局部CBF下降率明显高于双侧ACA区在MCA区，在分流开放前，1-CBF随PCO 2增加而增加。然而，在打开分流器后，1-CBF并不依赖于PCO 2而增加。我们成功地建立了一种新的实验模型，该模型具有局部低灌注区，并伴有CO2反应性的紊乱，这将有助于脑动静脉瘘血流动力学的评价。但该模型并非AVM模型，因此必须明确动静脉瘘与AVM的区别。

Hemodynamics in cerebral arteriovenous malformation (AVM) remains controversial, and the experimental model of AVM is not established. We developed the animal model of intracranial A-V shunt which revealed a focal hypoperfusion.A femoral vein graft was anastomosed end-to-side between a cortical branch of the middle cerebral artery (MCA) and the superior sagittal sinus (SSS).Using this model, the change of CBF was recorded before and after opening the shunt in the MCA territory where the anastomosis was done, as well as bilateral anterior cerebral artery (ACA) territories.In addition, the CO2 reactivity of the cerebral vessels before and after opening the shunt were examined by 5% CO2 inhalation technique in the MCA territory.The decreased rate of the local CBF in the MCA territory was significantly higher than in the bilateral ACA territory.The CBF decreased as the shunt volume increased only in the MCA territory.In the MCA territory, before opening the shunt 1-CBF increased depending on PCO2. However after opening the shunt, 1-CBF didn't increase depending on PCO2. The PCO2 reactivity in the MCA territory was impaired after opening the shunt.We developed successfully a new experimental model that has local hypoperfusion area with disturbance of CO2 reactivity.This model will be useful for the evaluating hemodynamics in cerebral A-V fistula. But this model is not the model of AVM,then we must make clear the differentiation between A-V fistula and AVM.