PDF(Pubmed)
Abstract：
Transient ischemic attack (TIA) is an early warning sign of stroke and death, necessitating suitable animal models due to the associated clinical diagnostic challenges. In this study, we developed a TIA model using flexible spatially targeted photothrombosis combined with real-time blood flow imaging feedback. By modulating the excitation light using wavefront technology, we precisely created a square light spot (50 × 250 µm), targeted at the distal middle cerebral artery (dMCA). The use of laser speckle contrast imaging (LSCI) provided real-time feedback on the ischemia, while the excitation light was ceased upon reaching complete occlusion. Our results demonstrated that the photothrombus formed in the dMCA and spontaneously recanalized within 10 min (416.8 ± 96.4 s), with no sensorimotor deficits or infarction 24 h post-TIA. During the acute phase, ischemic spreading depression occurred in the ipsilateral dorsal cortex, leading to more severe ischemia and collateral circulation establishment synchronized with the onset of dMCA narrowing. Post-reperfusion, the thrombi were primarily in the sensorimotor and visual cortex, disappearing within 24 h. The blood flow changes in the dMCA were more indicative of cortical ischemic conditions than diameter changes. Our method successfully establishes a photochemical TIA model based on the dMCA, allowing for the dynamic observation and control of thrombus formation and recanalization and enabling real-time monitoring of the impacts on cerebral blood flow during the acute phase of TIA.
摘要：
短暂性脑缺血发作（TIA）是中风和死亡的早期预警信号，由于相关的临床诊断挑战，需要合适的动物模型。在这项研究中,我们利用灵活的空间靶向光血栓形成结合实时血流成像反馈,建立了TIA模型.通过使用波前技术调制激发光，我们精确地创造了一个方形光点(50×250µm)，针对远端大脑中动脉（dMCA）。激光散斑对比成像（LSCI）的使用提供了对缺血的实时反馈，而激发光在达到完全闭塞时停止。我们的结果表明，光血栓在dMCA中形成，并在10分钟（416.8±96.4s）内自发再通，TIA后24小时无感觉运动缺陷或梗塞。在急性期,缺血性播散性抑郁发生在同侧背侧皮质，导致更严重的缺血和侧支循环建立与dMCA狭窄的发生同步。再灌注后,血栓主要在感觉运动和视觉皮层，在24小时内消失。dMCA的血流变化比直径变化更能表明皮质缺血状况。我们的方法成功地建立了基于dMCA的光化学TIA模型，允许动态观察和控制血栓形成和再通，并能够实时监测TIA急性期对脑血流的影响。
